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Guevara-Vela JM, Rocha-Rinza T, Rodríguez-Kessler PL, Muñoz-Castro A. On the structure and electronic properties of Pt n clusters: new most stable structures for n = 16-17. Phys Chem Chem Phys 2023; 25:28835-28840. [PMID: 37853760 DOI: 10.1039/d3cp04455f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
The lowest energy structures and electronic properties of Ptn clusters up to n = 17 are investigated by using a genetic algorithm in combination with density functional theory calculations. There are several putative global minimum structures for platinum clusters which have been reported by using different approaches, but a comprehensive study for n = 15-17 has not been carried out so far. Herein, we perform a consensus using GGA (PBE), meta-GGA (TPSS) and hybrid (B3PW91, PBE0, PBEh-3c, M06-L) functionals in conjunction with the Def2-TZVP basis set. New most stable structures are found for Pt16 and Pt17, which are slightly lower in energy than the previously reported global minima. Molecular dynamics simulations show that the clusters are rigid at room temperature. We analyze the structural, electronic, energy and vibrational data of the investigated clusters in detail.
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Affiliation(s)
| | - Tomás Rocha-Rinza
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Delegación Coyoacán, México City C.P. 04510, Mexico
| | - Peter L Rodríguez-Kessler
- Centro de Investigaciones en Óptica A.C., Loma del Bosque 115, Col. Lomas del Campestre, León, Guanajuato, Mexico.
| | - Alvaro Muñoz-Castro
- Facultad de Ingeniería, Arquitectura y Diseño, Universidad San Sebastián, Bellavista 7, Santiago, 8420524, Chile.
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2
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Rodríguez-Kessler PL, Muñoz-Castro A, Rodríguez-Domínguez AR, Cabellos JL. Structure effects of Pt 15 clusters for the oxygen reduction reaction: first-principles calculations. Phys Chem Chem Phys 2023; 25:4764-4772. [PMID: 36692089 DOI: 10.1039/d2cp05188e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In the present work, the lowest energy structures and electronic properties of Pt15 clusters are investigated using molecular dynamics simulations. The results showed that the most stable configuration is a capped pyramidal structure, which is 0.8 kal mol-1 lower in energy than a layered structure previously reported [V. Kumar and Y. Kawazoe, Evolution of Atomic and Electronic Structure of Pt Clusters: Planar, Layered, Pyramidal, Cage, Cubic, and Octahedral Growth, Phys. Rev. B: Condens. Matter Mater. Phys., 2008, 77, 205418.]. The result is further confirmed by using both the PW91/cc-pVDZ-PP and PBE/PW approaches including the other representative isomers for Pt15. Due to the interesting structure arrangements found, we have investigated the catalytic activities for the oxygen reduction reaction. We found that the most stable Pt15 clusters are plausible catalyts for the ORR according to their interaction with oxygen species, which is consistent with experiments of Pt clusters with atomicity below 20. The results of the structure, electronic, adsorption and vibrational properties of the clusters are provided.
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Affiliation(s)
- Peter L Rodríguez-Kessler
- Centro de Investigaciones en Óptica A.C. (CIO), Loma del Bosque 115, Col. Lomas del Campestre, León, Guanajuato, 37150, Mexico.
| | - Alvaro Muñoz-Castro
- Facultad de Ingeniería, Arquitectura y Diseño, Universidad San Sebastián, Bellavista 7, Santiago, 8420524, Chile.
| | - Adán R Rodríguez-Domínguez
- Universidad Politécnica de Tapachula, Carretera Tapachula a Puerto Madero km 24 + 300, San Benito, Puerto Madero C.P., 30830 Tapachula, Chiapas, Mexico
| | - José Luis Cabellos
- Instituto de Física, Universidad Autónoma de San Luis Potosí, San Luis Potosí 78000, Mexico
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3
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Merriles DM, Tomchak KH, Ewigleben JC, Morse MD. Predissociation measurements of the bond dissociation energies of EuO, TmO, and YbO. J Chem Phys 2021; 155:144303. [PMID: 34654298 DOI: 10.1063/5.0068543] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The observation of a sharp predissociation threshold in the resonant two-photon ionization spectra of EuO, TmO, and YbO has been used to measure the bond dissociation energies of these species. The resulting values, D0(EuO) = 4.922(3) eV, D0(TmO) = 5.242(6) eV, and D0(YbO) = 4.083(3) eV, are in good agreement with previous values but are much more precise. In addition, the ionization energy of TmO was measured by the observation of a threshold for one-color two-photon ionization of this species, resulting in IE(TmO) = 6.56(2) eV. The observation of a sharp predissociation threshold for EuO was initially surprising because the half-filled 4f7 subshell of Eu in its ground state generates fewer potential energy curves than in the other molecules we have studied by this method. The observation of a sharp predissociation threshold in YbO was even more surprising, given that the ground state of Yb is nondegenerate (4f146s2, 1Sg) and the lowest excited state of Yb is over 2 eV higher in energy. It is suggested that these molecules possess a high density of electronic states at the energy of the ground separated atom limit because ion-pair states drop below the ground limit, providing a sufficient electronic state density to allow predissociation to set in at the thermochemical threshold.
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Affiliation(s)
- Dakota M Merriles
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Kimberly H Tomchak
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Joshua C Ewigleben
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael D Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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Galindo-Uribe CD, Calaminici P, Cruz-Martínez H, Cruz-Olvera D, Solorza-Feria O. First-principle study of the structures, growth pattern, and properties of (Pt 3Cu) n, n = 1-9, clusters. J Chem Phys 2021; 154:154302. [PMID: 33887945 DOI: 10.1063/5.0045203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In this work, a first-principles systematic study of (Pt3Cu)n, n = 1-9, clusters was performed employing the linear combination of Gaussian-type orbital auxiliary density functional theory approach. The growth of the clusters has been achieved by increasing the previous cluster by one Pt3Cu unit at a time. To explore in detail the potential energy surface of these clusters, initial structures were obtained from Born-Oppenheimer molecular dynamics trajectories generated at different temperatures and spin multiplicities. For each cluster size, several dozens of structures were optimized without any constraints. The most stable structures were characterized by frequency analysis calculations. This study demonstrates that the obtained most stable structures prefer low spin multiplicities. To gain insight into the growing pattern of these systems, average bond lengths were calculated for the lowest stable structures. This work reveals that the Cu atoms prefer to be together and to localize inside the cluster structures. Moreover, these systems tend to form octahedra moieties in the size range of n going from 4 to 9 Pt3Cu units. Magnetic moment per atom and spin density plots were obtained for the neutral, cationic, and anionic ground state structures. Dissociation energies, ionization potential, and electron affinity were calculated, too. The dissociation energy and the electron affinity increase as the number of Pt3Cu units grows, whereas the ionization potential decreases.
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Affiliation(s)
- Carlos Daniel Galindo-Uribe
- Departamento de Química, CINVESTAV, Av. Instituto Politécnico Nacional 2508, San Pedro Zacatenco, Gustavo A. Madero, CP 07360 Mexico City, Mexico
| | - Patrizia Calaminici
- Departamento de Química, CINVESTAV, Av. Instituto Politécnico Nacional 2508, San Pedro Zacatenco, Gustavo A. Madero, CP 07360 Mexico City, Mexico
| | - Heriberto Cruz-Martínez
- Departamento de Química, CINVESTAV, Av. Instituto Politécnico Nacional 2508, San Pedro Zacatenco, Gustavo A. Madero, CP 07360 Mexico City, Mexico
| | - Domingo Cruz-Olvera
- Departamento de Química, CINVESTAV, Av. Instituto Politécnico Nacional 2508, San Pedro Zacatenco, Gustavo A. Madero, CP 07360 Mexico City, Mexico
| | - Omar Solorza-Feria
- Departamento de Química, CINVESTAV, Av. Instituto Politécnico Nacional 2508, San Pedro Zacatenco, Gustavo A. Madero, CP 07360 Mexico City, Mexico
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Xie WF, Zhu HR, Wei SH. Geometric and electronic properties of Au lPt m ( l + m ≤ 10) clusters: a first-principles study. Phys Chem Chem Phys 2021; 23:3050-3062. [PMID: 33491018 DOI: 10.1039/d0cp05642a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structural evolutions and electronic properties of AulPtm (l + m ≤ 10) clusters are investigated by using the first-principles methods. We use the inverse design of materials using the multi-objective differential evolution (IM2ODE) package to globally search the equilibrium structures and investigate the evolving trend from a two-dimensional structure to a three-dimensional structure on horizontal extension and vertical extension for AulPtm (l + m ≤ 10) clusters. The three-dimensional stable geometry of Au8Pt and Au8Pt2 is discovered for the first time in our work. We also notice that the equilibrium structures of AulPtm (l + m = 10 and l ≤ 8) tend to form a tetrahedral geometry and can be obtained by replacing the Au atom in the most stable structure of Aul+1Ptm-1 with the Pt atom, where Pt atoms assemble together and occupy the center of clusters and Au atoms prefer to lie on the vertex or edge position. The average binding energy (Eb) is mostly decided by Pt-Pt bond numbers, namely the numbers of Pt atoms, followed by Au-Pt bond numbers. The second-order energy difference (Δ2Ev and Δ2Eh) and the nearest-neighbor energy difference (Δ4Enn) show that Au6Pt, Au4Pt2, Au3Pt3, Au2Pt4 and AuPt7 clusters exhibit high relative physical stability, so we suggest that these clusters could be defined as the magic number clusters for AulPtm (l + m ≤ 10) clusters. The HOMO-LUMO energy gap (Eg), adiabatic ionization potential (AIP) and the adiabatic electron affinity (AEA) are also investigated to elaborate the relative electronic stability of all the clusters.
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Affiliation(s)
- Wei-Feng Xie
- Department of Microelectronic Science and Engineering, School of Physical Science and Technology, Ningbo University, Ningbo 315211, China. and College of Electronic Information and Optical Engineering, Nankai University, Tianjin, 300350, China
| | - Hao-Ran Zhu
- Department of Microelectronic Science and Engineering, School of Physical Science and Technology, Ningbo University, Ningbo 315211, China. and College of Electronic Information and Optical Engineering, Nankai University, Tianjin, 300350, China
| | - Shi-Hao Wei
- Department of Microelectronic Science and Engineering, School of Physical Science and Technology, Ningbo University, Ningbo 315211, China.
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Quinson J, Jensen KM. From platinum atoms in molecules to colloidal nanoparticles: A review on reduction, nucleation and growth mechanisms. Adv Colloid Interface Sci 2020; 286:102300. [PMID: 33166723 DOI: 10.1016/j.cis.2020.102300] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/25/2020] [Accepted: 10/26/2020] [Indexed: 12/24/2022]
Abstract
Platinum (Pt) is one of the most studied materials in catalysis today and considered for a wide range of applications: chemical synthesis, energy conversion, air treatment, water purification, sensing, medicine etc. As a limited and non-renewable resource, optimized used of Pt is key. Nanomaterial design offers multiple opportunities to make the most of Pt resources down to the atomic scale. In particular, colloidal syntheses of Pt nanoparticles are well documented and simple to implement, which accounts for the large interest in research and development. For further breakthroughs in the design of Pt nanomaterials, a deeper understanding of the intricate synthesis-structures-properties relations of Pt nanoparticles must be obtained. Understanding how Pt nanoparticles form from molecular precursors is both a challenging and rewarding area of investigation. It is directly relevant to develop improved Pt nanomaterials but is also a source of inspiration to design other precious metal nanostructures. Here, we review the current understanding of Pt nanoparticle formation. This review is aimed at readers with interest in Pt nanoparticles in general and their colloidal syntheses in particular. Readers with a strongest interest on the study of nanomaterial formation will find here the case study of Pt. The preferred model systems and characterization techniques used to perform the study of Pt nanoparticle syntheses are discussed. In light of recent achievements, further direction and areas of research are proposed.
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Abstract
Privileged structures is a term that is used in drug design to indicate a fragment that is popular in the population of drugs or drug candidates that are in the application or investigation phases, respectively. Privileged structures are popular motifs because they generate efficient drugs. Similarly, some elements appear to be more efficient and more popular in catalyst design and development. To indicate this fact, we use here a term privileged metal combination. In particular, Ru-based catalysts have paved a bumpy road in a variety of commercial applications from ammonia synthesis to carbon (di)oxide methanation. Here, we review Ru/Ni combinations in order to specifically find applications in environmental nanocatalysis and more specifically in carbon (di)oxide methanation. Synergy, ensemble and the ligand effect are theoretical foundations that are used to explain the advantages of multicomponent catalysis. The economic effect is another important issue in blending metal combinations. Low temperature and photocatalytic processes can be indicated as new tendencies in carbon (di)oxide methanation. However, due to economics, future industrial developments of this reaction are still questionable.
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Merriles DM, Sevy A, Nielson C, Morse MD. The bond dissociation energy of VO measured by resonant three-photon ionization spectroscopy. J Chem Phys 2020; 153:024303. [PMID: 32668947 DOI: 10.1063/5.0014006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The predissociation threshold of VO has been measured using resonant three-photon ionization (R3PI) spectroscopy. Given the high density of electronic states in the molecule, it is argued that the molecule dissociates rapidly as soon as the thermochemical bond dissociation energy (BDE) is exceeded, allowing the measured predissociation threshold to be assigned as the BDE. This is the first time a BDE has been measured using the R3PI method. The first photon is provided by an optical parametric oscillator (OPO) laser that promotes VO into a high-energy, discrete vibronic state. A tunable dye laser then excites the molecule further to a resonant state close to the dissociation limit where there is a quasi-continuum of states. A second photon from the same dye laser pulse ionizes the molecule, generating VO+ ions. The dye laser is then scanned to higher energies, and when the energy of one OPO photon plus one dye photon exceeds the BDE, the molecule dissociates before another dye photon can be absorbed to induce ionization. The combined photon energy at the sharp drop in the ion signal is assigned as the BDE. The experiment has been repeated using four different intermediate states, all yielding the same BDE, D0(VO) = 6.545(2) eV. Using thermochemical cycles, a revised value for the BDE of cationic VO is obtained, D0(V+-O) = 6.053(2) eV. The 0 K enthalpy of formation for VO(g) is also derived as ΔfH0K 0VO(g) = 128.6(1.0) kJ mol-1. Previous spectroscopic and thermochemical studies of VO are reviewed.
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Affiliation(s)
- Dakota M Merriles
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Andrew Sevy
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Christopher Nielson
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael D Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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Sorensen JJ, Tieu E, Morse MD. Bond dissociation energies of the diatomic late transition metal sulfides: RuS, OsS, CoS, RhS, IrS, and PtS. J Chem Phys 2020; 152:244305. [PMID: 32610999 DOI: 10.1063/5.0011754] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The spectra of RuS, OsS, CoS, RhS, IrS, and PtS have been recorded near their respective bond dissociation energies using resonant two-photon ionization spectroscopy. The spectra display an abrupt drop to baseline when the bond dissociation energy (BDE) is exceeded. It is argued that spin-orbit and nonadiabatic interactions among the myriad of states that result from the ground and low-lying separated atom limits cause the molecules to predissociate rapidly as soon as the ground separated atom limit is exceeded in energy. Thus, the observed sharp predissociation thresholds are assigned as the 0 K BDEs of the molecules. With this assumption, the BDEs are assigned as follows: 4.071(8) eV (RuS), 4.277(3) eV (OsS), 3.467(5) eV (CoS), 3.611(3) eV (RhS), 4.110(3) eV (IrS), and 4.144(8) eV (PtS). Using thermochemical cycles, the gas-phase enthalpies of formation at 0 K, ΔfH0 K°, were calculated to be 531.8(4.3) kJ mol-1 (RuS), 651.2(6.3) kJ mol-1 (OsS), 365.3(2.2) kJ mol-1 (CoS), 481.5(2.1) kJ mol-1 (RhS), 546.7(6.3) kJ mol-1 (IrS), and 438.9(1.5) kJ mol-1 (PtS). The ionization energies of RuS, CoS, and RhS were also calculated using data on the BDEs of the associated cations and were found to be 8.39(10) eV (RuS), 8.40(9) eV (CoS), and 8.46(12) eV (RhS). Combining these data with predissociation measurements of other transition metal sulfide BDEs, the periodic trends in the transition metal sulfide BDEs are discussed and the BDEs of the transition metal sulfides are compared to those of the corresponding selenides. The BDEs of the sulfides are found to be 15.4% greater than those of the corresponding sulfides.
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Affiliation(s)
- Jason J Sorensen
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Erick Tieu
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael D Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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Wu X, Wang GY, Du RB, Tang S. Structures, stabilities and electronic properties of Pt-Rh clusters based on DFT and Sutton-Chen potential. Chem Phys 2020. [DOI: 10.1016/j.chemphys.2020.110751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Sorensen JJ, Tieu E, Morse MD. Bond dissociation energies of diatomic transition metal selenides: ScSe, YSe, RuSe, OsSe, CoSe, RhSe, IrSe, and PtSe. J Chem Phys 2020; 152:124305. [PMID: 32241137 DOI: 10.1063/5.0003136] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The diatomic transition metal selenides, MSe (M = Sc, Y, Ru, Os, Co, Rh, Ir, and Pt), were studied by resonant two-photon ionization spectroscopy near their respective bond dissociation energies. As these molecules exhibit high densities of vibronic states near their dissociation limits, the spectra typically appear quasicontinuously at these energies. Spin-orbit and nonadiabatic couplings among the multitudes of potential curves allow predissociation to occur on a rapid timescale when the molecule is excited to states lying above the ground separated atom limit. This dissociation process occurs so rapidly that the molecules are dissociated before they can be ionized by the absorption of a second photon. This results in an abrupt drop in the ion signal that is assigned as the 0 K bond dissociation energy for the molecule, giving bond dissociation energies of 4.152(3) eV (ScSe), 4.723(3) eV (YSe), 3.482(3) eV (RuSe), 3.613(3) eV (OsSe), 2.971(6) eV (CoSe), 3.039(9) eV (RhSe), 3.591(3) eV (IrSe), and 3.790(31) eV (PtSe). The enthalpies of formation, ΔfH0K° (g), for each diatomic metal selenide were calculated using thermochemical cycles, yielding ΔfH0K° (g) values of 210.9(4.5) kJ mol-1 (ScSe), 203.5(4.5) kJ mol-1 (YSe), 549.2(4.5) kJ mol-1 (RuSe), 675.9(6.5) kJ mol-1 (OsSe), 373.9(2.6) kJ mol-1 (CoSe), 497.4(2.7) kJ mol-1 (RhSe), 557.4(6.5) kJ mol-1 (IrSe), and 433.7(3.6) kJ mol-1 (PtSe). Utilizing a thermochemical cycle, the ionization energy for ScSe is estimated to be about 7.07 eV. The bonding trends of the transition metal selenides are discussed.
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Affiliation(s)
- Jason J Sorensen
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Erick Tieu
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael D Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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Zhao Z, Li Z, Wang Q. Structures, electronic and magnetic properties of transition metal atoms encapsulated in B12N12 cage. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2019.136922] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Merriles DM, Tieu E, Morse MD. Bond dissociation energies of FeB, CoB, NiB, RuB, RhB, OsB, IrB, and PtB. J Chem Phys 2019; 151:044302. [DOI: 10.1063/1.5113511] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Dakota M. Merriles
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Erick Tieu
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael D. Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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14
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Abstract
A fundamental need in chemistry is understanding the chemical bond, for which the most quantitative measure is the bond dissociation energy (BDE). While BDEs of chemical bonds formed from the lighter main group elements are generally well-known and readily calculated by modern computational chemistry, chemical bonds involving the transition metals, lanthanides, and actinides remain computationally extremely challenging. This is due to the simultaneous importance of electron correlation, spin-orbit interaction, and other relativistic effects, coupled with the large numbers of low-lying states that are accessible in systems with open d or f subshells. The development of efficient and accurate computational methods for these species is currently a major focus of the field. An obstacle to this effort has been the scarcity of highly precise benchmarks for the BDEs of M-X bonds. For most of the transition metal, lanthanide, or actinide systems, tabulated BDEs of M-X bonds have been determined by Knudsen effusion mass spectrometric measurements of high-temperature equilibria. The measured ion signals are converted to pressures and activities of the species involved in the equilibrium, and the equilibrium constants are then analyzed using a van't Hoff plot or the third-law method to extract the reaction enthalpy, which is extrapolated to 0 K to obtain the BDE. This procedure introduces errors at every step and ultimately leads to BDEs that are typically uncertain by 2-20 kcal mol-1 (0.1-1 eV). A second method in common use employs a thermochemical cycle in which the ionization energies of the MX molecule and M atom are combined with the BDE of the M+-X bond, obtained via guided ion beam mass spectrometry, to yield the BDE of the neutral, M-X. When accurate values of all three components of the cycle are available, this method yields good results-but only rarely are all three values available. We have recently implemented a new method for the precise measurement of BDEs in molecules with large densities of electronic states that is based on the rapid predissociation of these species as soon as the ground separated atom limit is exceeded. When a sharp predissociation threshold is observed, its value directly provides the BDE of the system. With this method, we are able in favorable cases to determine M-X BDEs to an accuracy of ∼0.1 kcal mol-1 (0.004 eV). The method is generally applicable to species that have a high density of states at the ground separated atom limit and has been used to measure the BDEs of more than 50 transition metal-main group MX molecules thus far. In addition, a number of metal-metal BDEs have also been measured with this method. There are good prospects for the extension of the method to polyatomic systems and to lanthanide and actinide-containing molecules. These precise BDE measurements provide chemical trends for the BDEs across the transition metal series, as well as crucial benchmarks for the development of efficient and accurate computational methods for the d- and f-block elements.
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Affiliation(s)
- Michael D. Morse
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
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Xie WF, Zhu HR, Wei SH, Hua DY. Catalytic reduction of SO 2 by CO over Au 4Pt 2(CO) n and Au 6Pt(CO) n clusters: a first-principles study. Phys Chem Chem Phys 2017; 19:29278-29286. [PMID: 29068009 DOI: 10.1039/c7cp04740a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The catalytic properties of the magic gold-platinum bimetallic clusters (Au4Pt2 and Au6Pt) for the reduction of SO2 by CO, without or with preadsorbing CO molecules, are firstly investigated using density functional theory calculations. We find that the catalytic activities improve effectively with the preadsorption of CO onto the catalysts and that the catalytic activities of Au6Pt(CO)n are better than those of Au4Pt2(CO)n as more CO molecules are adsorbed onto the catalysts. During the reaction process, the Au4Pt2(CO)n clusters always keep two-dimensional morphologies except for when n = 5 and the Au6Pt(CO)n clusters have three-dimensional geometries except for when n = 0. The most stable adsorption site for SO2 molecules on the catalysts is the site of preadsorbing the next CO molecule on the corresponding catalysts. The largest activation energy (E) is related to the metal 5d (M-5d) band center and the charge transfer (Ct) as well as the bond length (Rb) between COS and the catalyst contribute to the desorption energy (Ed) of COS corporately. We propose that Au6Pt(CO)6 is a cost-effective gold-platinum bimetallic catalyst for the reduction of SO2 by CO.
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Affiliation(s)
- Wei-Feng Xie
- Department of Microelectronic Science and Engineering, Faculty of Science, Ningbo University, Ningbo 315211, China.
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16
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Chi Y, Zhao L, Zhu H, Guo W. Effect of alloying on the catalytic properties of Pt–Ni bimetallic subnanoclusters: a theoretical investigation. Theor Chem Acc 2017. [DOI: 10.1007/s00214-017-2141-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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17
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Vila FD, Rehr JJ, Nuzzo RG, Frenkel AI. Anomalous Structural Disorder in Supported Pt Nanoparticles. J Phys Chem Lett 2017; 8:3284-3288. [PMID: 28669195 DOI: 10.1021/acs.jpclett.7b01446] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Supported Pt nanocatalysts generally exhibit anomalous behavior, including negative thermal expansion and large structural disorder. Finite temperature DFT/MD simulations reproduce these properties, showing that they are largely explained by a combination of thermal vibrations and low-frequency disorder. We show here that a full interpretation is more complex and that the DFT/MD mean-square relative displacements (MSRD) can be further separated into vibrational disorder, "dynamic structural disorder" (DSD), and long-time equilibrium fluctuations of the structure dubbed "anomalous structural disorder" (ASD). We find that the vibrational and DSD components behave normally, increasing linearly with temperature while the ASD decreases, reflecting the evolution of mean nanoparticle geometry. As a consequence the usual procedure of fitting the MSRD to normal vibrations plus temperature-independent static disorder results in unphysical bond strengths and Grüneisen parameters.
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Affiliation(s)
- Fernando D Vila
- Department of Physics, University of Washington , Seattle, Washington 98195, United States
| | - John J Rehr
- Department of Physics, University of Washington , Seattle, Washington 98195, United States
| | - Ralph G Nuzzo
- Department of Chemistry, University of Illinois , Urbana, Illinois 61801, United States
| | - Anatoly I Frenkel
- Department of Materials Science and Chemical Engineering, Stony Brook University , Stony Brook, New York 11794, United States
- Division of Chemistry, Brookhaven National Laboratory , Upton, New York 11973, United States
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Affiliation(s)
- Jingyue Liu
- Department of Physics, Arizona State University, Tempe, Arizona 85287, United States
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Lu J, Wei SH, Zhang YY, Hua DY, Duan XM. Geometric, electronic and magnetic properties of Aun, Aun−1Pt and Aun−2Pt2 (n=2–9) clusters: A first-principles study. COMPUT THEOR CHEM 2016. [DOI: 10.1016/j.comptc.2016.06.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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20
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Johnson EL, Davis QC, Morse MD. Predissociation measurements of bond dissociation energies: VC, VN, and VS. J Chem Phys 2016; 144:234306. [DOI: 10.1063/1.4953782] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Eric L. Johnson
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Quincy C. Davis
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael D. Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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21
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Matthew DJ, Oh SH, Sevy A, Morse MD. The bond length and bond energy of gaseous CrW. J Chem Phys 2016; 144:214306. [DOI: 10.1063/1.4952453] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Daniel J. Matthew
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Sang Hoon Oh
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Andrew Sevy
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael D. Morse
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, USA
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22
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Li A, Guo L, An X. CO oxidation catalyzed by Al n Pt (n = 1–11) clusters: A density functional theory simulations. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2015. [DOI: 10.1134/s003602441512002x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Long N, Du J, Jiang G. The influence of the composition of eight-atom Pt–Ir clusters on the magnetic properties. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1046530] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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24
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Martins L, Jorge F, Machado S. All-electron segmented contraction basis sets of triple zeta valence quality for the fifth-row elements. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1040095] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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25
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Pašti IA, Baljozović MR, Granda-Marulanda LP, Skorodumova NV. Bimetallic dimers adsorbed on a defect-free MgO(001) surface: bonding, structure and reactivity. Phys Chem Chem Phys 2015; 17:9666-79. [PMID: 25660349 DOI: 10.1039/c4cp05723f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A large number of computational studies have been devoted to the investigation of monometallic clusters supported by MgO. However, in practice, catalysis shows that multicomponent catalytic systems often win in catalytic performance over single component systems. In this study, the geometrical and electronic structure, stability and chemisorption properties of M1M2 metal dimers (M1, M2 = Ru, Rh, Pd, Ir, Pt) supported by defect free MgO(001) have been investigated in the framework of density functional theory. The oxygen sites of MgO(001) are the preferred adsorption sites for all the studied clusters, the majority of them adsorbing parallel to the surface with metal atoms attached to two surface oxygen atoms. The energetics of M1M2 + MgO(001) formation shows that the adsorption complexes are stable and benefit from metal-oxygen and metal-metal interaction. The chemisorption properties of Pd and Pt atoms in PdM2 and PtM2 dimers are studied using CO as a probe molecule. A linear relationship between the CO chemisorption and the d-band center position of the reacting atom in the dimer is observed, extending the d-band center model to the case of highly under-coordinated metal atoms supported by a non-conductive material.
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Affiliation(s)
- Igor A Pašti
- Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11158 Belgrade, Serbia.
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26
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Singh NB, Sarkar U. Structure, vibrational, and optical properties of platinum cluster: a density functional theory approach. J Mol Model 2014; 20:2537. [PMID: 25451143 DOI: 10.1007/s00894-014-2537-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 11/17/2014] [Indexed: 11/26/2022]
Abstract
Using density functional theory, stability, chemical, and optical properties of small platinum clusters, Ptn (n = 2 to 10) have been investigated. An attempt has been made to establish a correlation between stability and chemical reactivity parameters. The calculated geometries are in agreement with the available experimental and theoretical results. The atom addition energy change (ΔE1) and stability function (ΔE2) reveal that Pt7 is more stable than its neighboring clusters. Very good agreement of the calculated electron affinity with the available experimental results has been observed. The polarizability of the Ptn clusters depends almost linearly on the number of atoms. A correlation between the static polarizability and ionization potential is found, paving a way to calculate polarizabilty of larger clusters from their ionization potential. The calculated vibrational frequencies are compared with available experimental and theoretical results and good agreement between them has been established. In general, the prominent peak of molar absorption coefficient is shifting toward the lower energy side when cluster size grows. Our DOS calculation suggests that d orbital is primarily responsible for HOMO position and s orbital is responsible for LUMO position.
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27
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Chaves AS, Rondina GG, Piotrowski MJ, Tereshchuk P, Da Silva JLF. The Role of Charge States in the Atomic Structure of Cun and Ptn (n = 2–14 atoms) Clusters: A DFT Investigation. J Phys Chem A 2014; 118:10813-21. [DOI: 10.1021/jp508220h] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
| | | | - Maurício J. Piotrowski
- Departamento
de Física, Universidade Federal de Pelotas, Caixa Postal 354, 96010-900 Pelotas, Rio Grande
do Sul, Brazil
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28
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Hamad B, El-Bayyari Z, Marashdeh A. Investigation of the stability of platinum clusters and the adsorption of nitrogen monoxide: First principles calculations. Chem Phys 2014. [DOI: 10.1016/j.chemphys.2014.07.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Mahmoodinia M, Ebadi M, Åstrand PO, Chen D, Cheng HY, Zhu YA. Structural and electronic properties of the Pt(n)-PAH complex (n = 1, 2) from density functional calculations. Phys Chem Chem Phys 2014; 16:18586-95. [PMID: 25076458 DOI: 10.1039/c4cp02488e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A detailed density functional study of the Pt atom and the Pt dimer adsorption on a polyaromatic hydrocarbon (PAH) is presented. The preferred adsorption site for a Pt atom is confirmed to be the bridge site. Upon adsorption of a single Pt atom, however, it is found here that the electronic ground state changes from the triplet state (5d(9)6s(1) configuration) to the closed-shell singlet state (5d(10)6s(0) configuration), which consequently will affect the catalytic activity of Pt when single Pt atoms bind to a carbon surface. The preferred adsorption site for the Pt dimer in the upright configuration is the hollow site. In contrast to the adsorption of a single Pt atom, the formation of a Pt-C bond in the adsorption of a Pt dimer is not accompanied by a change in the spin state, so the most stable electronic state is still the triplet state. While the atomic charge on the Pt atoms and dimers (in parallel configuration) in the Ptn-PAH complex is positive, a negative charge is found on the upper Pt atom for the upright configuration, indicating that single layers of Pt atoms will have a different catalytic activity as compared to Pt clusters on a carbon surface. Comparing the Pt-C bond length and the charge transfer on different sites, the magnitude of the charge transfer decreases with bond elongation, indicating that the catalytic activity of the Pt atom and dimer can be changed by modifying its chemical surroundings. The adsorption energy for the Pt dimer on a PAH surface is larger than that for two individual Pt atoms on the surface indicating that aggregation of Pt atoms on the PAH surface is favorable.
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Affiliation(s)
- Mehdi Mahmoodinia
- Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
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30
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31
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Zhang X, Guo L, Guo J, Ren NN. Density functional theory study of the structures, electronic states and stabilities of Al n Pt (n = 1–15) clusters. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2014. [DOI: 10.1134/s0036024414030273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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32
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Theoretical Studies of the Electronic Structures and Spectrum Properties of Pt n Ni m (n + m = 7, n, m ≠ 0) Clusters. J CLUST SCI 2013. [DOI: 10.1007/s10876-013-0580-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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33
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Activation of propane C–H and C–C bonds by a diplatinum cluster: potential energy surfaces and reaction mechanisms. Struct Chem 2013. [DOI: 10.1007/s11224-013-0311-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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34
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Ju TY, Yang HQ, Li FM, Li XY, Hu CW. Reaction mechanism on the activation of ethane C–H and C–C bonds by a diplatinum cluster. Theor Chem Acc 2013. [DOI: 10.1007/s00214-013-1387-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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35
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Shore TC, Mith D, DePrekel D, McNall S, Ge Y. A B3LYP study on the C–H activation in propane by neutral and +1 charged low-energy platinum clusters with 2–6 atoms. REACTION KINETICS MECHANISMS AND CATALYSIS 2013. [DOI: 10.1007/s11144-013-0572-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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36
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Proch S, Wirth M, White HS, Anderson SL. Strong Effects of Cluster Size and Air Exposure on Oxygen Reduction and Carbon Oxidation Electrocatalysis by Size-Selected Ptn (n ≤ 11) on Glassy Carbon Electrodes. J Am Chem Soc 2013; 135:3073-86. [DOI: 10.1021/ja309868z] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Sebastian Proch
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112,
United States
| | - Mark Wirth
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112,
United States
| | - Henry S. White
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112,
United States
| | - Scott L. Anderson
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112,
United States
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37
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The effect of alloying on the H-atom adsorption on the (100) surfaces of Pd-Ag, Pd-Pt, Pd-Au, Pt-Ag, and Pt-Au. A theoretical study. OPEN CHEM 2011. [DOI: 10.2478/s11532-011-0028-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThe effect of alloying on the adsorption of atomic hydrogen was studied using density functional theory (DFT). In the study the (100) surfaces of Pd-Ag, Pd-Pt, Pd-Au, Pt-Ag, and Pt-Au alloys were considered by means of a cluster model. The structural and energetic properties of the H atom adsorbed on the Pd4Me (Me = Ag, Pt, Au) and Pt4Me (Me = Pd, Ag, Au) clusters were calculated and compared with the H-atom adsorption on monometallic clusters. The effect of alloying on the H-atom adsorption is evident for all the investigated bimetallic systems. However, it strongly depends on the second metal atom, Me, is placed in the surface layer or in the subsurface one. In general, the H atom adsorbed in a site containing the second metal exhibits different properties from those characteristic of its adsorption on Pd(100) and Pt(100). Hence, the modified interaction between atomic hydrogen and the alloyed surfaces may increase the selectivity of the catalytic hydrogenation reactions on such surfaces.
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38
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O'Brien LC, O’Brien JJ. The Pt2 (1,0) band of System VI in the near infrared by intracavity laser absorption spectroscopy. J Chem Phys 2011; 134:184304. [DOI: 10.1063/1.3589862] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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39
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Thayer JS. Relativistic Effects and the Chemistry of the Heavier Main Group Elements. CHALLENGES AND ADVANCES IN COMPUTATIONAL CHEMISTRY AND PHYSICS 2010. [DOI: 10.1007/978-1-4020-9975-5_2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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40
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Ončák M, Cao Y, Höckendorf R, Beyer M, Zahradník R, Schwarz H. Thermal NH Bond Activation on Anionic and Cationic Platinum Clusters: Non-Predetermined Reaction Pathways Indicate Transitions to a Bulk Surface Reactivity. Chemistry 2009; 15:8465-8474. [DOI: 10.1002/chem.200900677] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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41
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Franzreb K, Diez RP, Alonso JA. Observation of Zr22+, Cd22+, Hf22+, W22+, and Pt22+ in the gas phase. J Chem Phys 2009; 130:144312. [DOI: 10.1063/1.3112013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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42
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43
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Sebetci A. Does spin–orbit coupling effect favor planar structures for small platinum clusters? Phys Chem Chem Phys 2009; 11:921-5. [DOI: 10.1039/b810837d] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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44
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Gas-phase reactivities of charged platinum dimers with ammonia: A combined experimental/theoretical study. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2007.11.059] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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45
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46
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Xu Y, Shelton WA, Schneider WF. Effect of particle size on the oxidizability of platinum clusters. J Phys Chem A 2007; 110:5839-46. [PMID: 16640379 DOI: 10.1021/jp0547111] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The catalytic properties of transition metal particles often depend crucially on their chemical environment, but so far, little is known about how the effects of the environment vary with particle size, especially for clusters consisting of only a few atoms. To gain insight into this topic, we have studied the oxygen affinity of free Pt(x) clusters as a function of cluster size (x = 1, 2, 3, 4, 5, and 10) using density functional theory (DFT) calculations (GGA-PW91). DFT-based Nosé-Hoover molecular dynamics has been used to explore the configuration space of the Pt(x)O(x) and Pt(x)O(2x) clusters, leading to the discovery of several novel Pt-oxide structures. The formation of small Pt-oxide clusters by oxidizing the corresponding Pt(x) clusters is found to be significantly more exothermic than the formation of bulk Pt-oxides from Pt metal. The exothermicity generally increases as cluster size decreases but exhibits strongly nonlinear dependence on the cluster size. The nanoclusters are also structurally distinct from the bulk oxides and prefer one- and two-dimensional chain and ringlike shapes. These findings help elucidate the oxidation behavior of Pt nanoclusters and lay the foundation for understanding the reactivity of Pt nanoclusters in oxidizing chemical environments.
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Affiliation(s)
- Ye Xu
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Tennessee 37831, USA
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47
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Pawluk T, Xiao L, Yukna J, Wang L. Impact of PES on MD Results of the Coalescence of M2 + M with M = Ir, Pt, Au, Ag. J Chem Theory Comput 2007; 3:328-35. [DOI: 10.1021/ct600257p] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tiffany Pawluk
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois 62901
| | - Li Xiao
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois 62901
| | - Jennifer Yukna
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois 62901
| | - Lichang Wang
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois 62901
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49
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Saenz LR, Balbuena PB, Seminario JM. Platinum Testbeds: Interaction with Oxygen. J Phys Chem A 2006; 110:11968-74. [PMID: 17064185 DOI: 10.1021/jp064691i] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We develop testbeds to study catalytic reactions modeled using the minimum number of platinum atoms needed to have an acceptable description of the chemistry on a realistic platinum surface that may include the contribution from a bulk continuum or may simply represent a local site on a nanocluster. In this particular case, the requirement is that a stable cluster may be connected to a stable bulk with equivalent highest occupied molecular orbital and Fermi level, respectively. We focus our work on the interaction of platinum clusters with molecular oxygen, which yields a complex cluster-molecule with fully delocalized molecular orbitals in the neighborhood of the Fermi energy of platinum, responsible for the interesting catalytic behavior of this material.
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Affiliation(s)
- Lina R Saenz
- Department of Chemical Engineering, Texas A&M University, College Station, Texas, USA
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50
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Xia F, Cao Z. Relativistic DFT Studies of Dehydrogenation of Methane by Pt Cationic Clusters: Cooperative Effect of Bimetallic Clusters. J Phys Chem A 2006; 110:10078-83. [PMID: 16913681 DOI: 10.1021/jp062544e] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dehydrogenation reaction mechanisms of methane catalyzed by transition-metal clusters PtM(+) (M = Cu, Ag, Au) and Pt(n)(+) (n = 2-4) have been investigated theoretically. In the reactions of PtM(+) (M = Cu, Ag, Au) with CH(4), cleavage of the first C-H bond is quite facile without barrier. The second C-H bond activation and the release of H(2) from molecular complex are generally the rate-determining steps. In the reactions of platinum clusters Pt(n)()(+) (n = 2-4) with CH(4), the H(2) elimination from the dihydrogen complex is the rate-determining step. Spin crossover may occur in the reaction of Pt(2)(+) and CH(4). Pt(2)(+) and Pt(3)(+) can dehydrogenate methane efficiently due to remarkable thermodynamic stability of the products. The dehydrogenation of methane induced by Pt(4)(+) is less favored thermodynamically than Pt(n)()(+) (n = 1, 2, 3). On the basis of theoretical analyses, the differences in reactivity among the clusters and the nature of cooperative effect of the bimetallic cluster have been discussed. The calculated results provide a reasonable basis for understanding of experimental observations.
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Affiliation(s)
- Fei Xia
- Department of Chemistry and State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
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