1
|
Optical properties of GaAs nanocrystals: influence of an electric field. J Mol Model 2013; 19:2273-83. [PMID: 23377958 DOI: 10.1007/s00894-013-1753-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022]
Abstract
A study of the electronic and optical properties of the hydrogen-terminated GaAs nanocrystals Ga₆₈As₆₈H₉₆ and Ga₉₂As₈₀H₁₀₈ is presented. In this study, their dielectric functions, refractive indices, and absorption coefficients were calculated using density functional theory (DFT). The influence of a uniform external electric field on the optical properties of the nanocrystals was also explored. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) for each nanocrystal were studied in the absence and the presence of the uniform external electric field. Our results indicate that the HOMO-LUMO gap decreases with increasing electric field strength. The calculated density of states revealed that the main reason for this shrinking gap is an increase in the delocalization of the gallium π-orbitals under the influence of an increasing external electric field. The permanent dipole moment and the polarizability of the nanocrystals under the induced electric field increased with increasing nanocrystal radius. The induced electric field caused a noticeable redshift in the absorption peaks. The electric field also increased the absorption intensity, particularly when the field strength was >0.25 V/Å.
Collapse
|
2
|
Nanda KK. On the paradoxical relation between the melting temperature and forbidden energy gap of nanoparticles. J Chem Phys 2010; 133:054502. [DOI: 10.1063/1.3466920] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
3
|
Gutsev GL, O’Neal, Jr. RH, Saha BC, Mochena MD, Johnson E, Bauschlicher, Jr. CW. Optical Properties of (GaAs)n Clusters (n = 2−16). J Phys Chem A 2008; 112:10728-35. [DOI: 10.1021/jp803888k] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- G. L. Gutsev
- Department of Physics, Florida A&M University, Tallahassee, Florida 32307, Environmental Sciences Institute, Florida A & M University, Tallahassee, Florida 32307, and NASA Ames Research Center, Moffett Field, California 94035
| | - R. H. O’Neal, Jr.
- Department of Physics, Florida A&M University, Tallahassee, Florida 32307, Environmental Sciences Institute, Florida A & M University, Tallahassee, Florida 32307, and NASA Ames Research Center, Moffett Field, California 94035
| | - B. C. Saha
- Department of Physics, Florida A&M University, Tallahassee, Florida 32307, Environmental Sciences Institute, Florida A & M University, Tallahassee, Florida 32307, and NASA Ames Research Center, Moffett Field, California 94035
| | - M. D. Mochena
- Department of Physics, Florida A&M University, Tallahassee, Florida 32307, Environmental Sciences Institute, Florida A & M University, Tallahassee, Florida 32307, and NASA Ames Research Center, Moffett Field, California 94035
| | - E. Johnson
- Department of Physics, Florida A&M University, Tallahassee, Florida 32307, Environmental Sciences Institute, Florida A & M University, Tallahassee, Florida 32307, and NASA Ames Research Center, Moffett Field, California 94035
| | - C. W. Bauschlicher, Jr.
- Department of Physics, Florida A&M University, Tallahassee, Florida 32307, Environmental Sciences Institute, Florida A & M University, Tallahassee, Florida 32307, and NASA Ames Research Center, Moffett Field, California 94035
| |
Collapse
|
4
|
Wang J, Ma L, Zhao J, Wang G, Chen X, Bruce King R. Electronic and magnetic properties of manganese and iron-doped GanAsn nanocages (n=7–12). J Chem Phys 2008; 129:044908. [DOI: 10.1063/1.2960625] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
5
|
Gutsev GL, Johnson E, Mochena MD, Bauschlicher CW. The structure and energetics of (GaAs)n, (GaAs)n−, and (GaAs)n+ (n=2–15). J Chem Phys 2008; 128:144707. [DOI: 10.1063/1.2884860] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
6
|
Marchal R, Carbonnière P, Begue D, Pouchan C. Structural and vibrational determination of small gallium–arsenide clusters from CCSD(T) and DFT calculations. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2007.12.079] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
7
|
Karamanis P, Bégué D, Pouchan C. Ab initiofinite field (hyper)polarizability computations on stoichiometric gallium arsenide clusters GanAsn (n=2–9). J Chem Phys 2007; 127:094706. [PMID: 17824758 DOI: 10.1063/1.2768365] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report reliable ab initio finite field (hyper)polarizability values at Hartree-Fock and second order Moller-Plesset perturbation theory (MP2) levels of theory for different geometrical configurations of small gallium arsenide clusters Ga(n)As(n) with n=2-5. We relied on all-electron basis sets and pseudopotentials suitable for (hyper)polarizability calculations. In each case, we used structures that have been established in the literature after we optimized their geometries at B3LYP/cc-pVTZ-PP level of theory. Our results suggest that the first order hyperpolarizability (beta) is much more sensitive to the special geometric features than the second order hyperpolarizability (gamma). For the most stable configurations up to ten atoms the second order hyperpolarizability at MP2 level of theory varies between 15 x 10(4) and 32 x 10(4) e(4)a0 (4)Eh(-3). In addition, we examined the polarizability per atom evolution versus the cluster size for Ga(n)As(n) with n=2-9. Our work extends earlier theoretical studies which were limited to eight atoms and exposes that the polarizability/atom of the most stable stoichiometric configurations up to Ga(9)As(9) continues the monotonic downward trend with increasing size. Lastly, from the methodological point of view, our analysis shows that apart from polarizabilities, augmented pseudopotentials yield reliable first and second hyperpolarizability values as well.
Collapse
Affiliation(s)
- Panaghiotis Karamanis
- Institut Pluridisciplinaire en Recherche sur l'Environnement et les Matériaux, UMR 5254 CNRS, Equipe de Chimie Physique, Groupe de Chimie Théorique, IFR, Rue Jules Ferry, BP 27540, F-64075 PAU, Cedex, France
| | | | | |
Collapse
|
8
|
|
9
|
Zhu X. Jahn-Teller distortion geometries and electronic structures of Ga3Ge, GaGe3, and their ions. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:512-20. [PMID: 16872866 DOI: 10.1016/j.saa.2006.02.067] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Accepted: 02/25/2006] [Indexed: 05/11/2023]
Abstract
Computational studies on the geometric, electronic, and spectroscopic properties of electronic states are presented for GaGe3, Ga3Ge, and their ions using the CASSCF and DFT(B3LYP)/CCSD(T)/QCISD(T) techniques. The optimized geometries of electronic states, vibrational frequencies, energy separations, Mulliken populations, ionization energies, electron affinities, binding energies are obtained. The anion photoelectron spectra of GaGe3- and Ga3Ge- are predicted. In addition, the results from the low-lying states of GaGe3 and Ga3Ge are compared with those of GaSi3 and Ga3Si. Results demonstrate that the equilibrium geometries of most electronic states of GaGe3, Ga3Ge, and their ions exhibit Jahn-Teller distortion. It is interesting to find that there is not charge transfer between Ga and Ge atoms upon an electron attachment to the ground states of GaGe3 and Ga3Ge, while the amount of charge transfer between Ga and Ge atoms significantly increases upon an electron ionization from the ground state of Ga3Ge.
Collapse
Affiliation(s)
- Xiaolei Zhu
- Department of Chemistry, Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, PR China
| |
Collapse
|
10
|
Zhu X. Theoretical study of electronic structures and spectroscopic properties of Ga3Sn, GaSn3, and their ions. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:153-62. [PMID: 17010663 DOI: 10.1016/j.saa.2005.12.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Accepted: 12/05/2005] [Indexed: 05/12/2023]
Abstract
Ground and excited states of mixed gallium stannide tetramers (Ga3Sn, Ga3Sn+, Ga3Sn-, GaSn3, GaSn3+, and GaSn3-) are investigated employing the complete active space self-consistent-field (CASSCF), density function theory (DFT), and the coupled-cluster single and double substitution (including triple excitations) (CCSD(T)) methods. The ground states of Ga3Sn, Ga3Sn+, and Ga3Sn- are found to be the 2A1, 3B1, and 1A1 states in C2v symmetry with a planar quadrilateral geometry, respectively. The ground states of GaSn3 and GaSn3- is predicted to be the 2A1 and 1A1 states in C2v point group with a planar quadrilateral structure, respectively, while the ground state of GaSn3+ is the 1A1 state with ideal triangular pyramid C3v geometry. Equilibrium geometries, vibrational frequencies, binding energies, electron affinities, ionization energies, and other properties of Ga3Sn and GaSn3 are computed and discussed. The anion photoelectron spectra of Ga3Sn- and GaSn3- are also predicted. It is interesting to find that the amount of charge transfer between Ga and Sn2 atoms in the 1A1 state of GaSn3+ greatly increases upon electron ionization from the 2A1 state of GaSn3, which may be caused by large geometry change. On the other hand, the results of the low-lying states of Ga3Sn and GaSn3 are compared with those of Ga3Si and GaSi3.
Collapse
Affiliation(s)
- Xiaolei Zhu
- Department of Chemistry, Nanjing University of Technology, Nanjing 210009, PR China.
| |
Collapse
|
11
|
Lan YZ, Cheng WD, Wu DS, Shen J, Huang SP, Zhang H, Gong YJ, Li FF. A theoretical investigation of hyperpolarizability for small GanAsm (n+m=4–10) clusters. J Chem Phys 2006; 124:94302. [PMID: 16526852 DOI: 10.1063/1.2173993] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this paper, the second and third order polarizabilities of small Ga(n)As(m) (n + m=4-10) clusters are systematically investigated using the time dependent density functional theory (TDDFT)6-311+G* combined with the sum-over-states method (SOSTDDFT6-311+G*). For the static second order polarizabilities, the two-level term (beta(vec.2)) makes a significant contribution to the beta(vec) for all considered Ga(n)As(m) clusters except for the Ga3As4 cluster. And, for the static third order polarizabilities, the positive channel (gamma(II)) makes a larger contribution to gamma(tot) than the negative channel (gamma(I)). Similar to the cubic GaAs bulk materials, the small Ga(n)As(m) cluster assembled materials exhibit large second order (1 x 10(-6) esu) and third order susceptibilities (5 x 10(-11) esu). The dynamic behavior of beta(-2omega; omega, omega) and gamma(-3omega; omega, omega, omega) show that the small Ga(n)As(m) cluster will be a good candidate of nonlinear optical materials due to the avoidance of linear resonance photoabsorption.
Collapse
Affiliation(s)
- Y-Z Lan
- Fujian Institute of Research on the Structure of Matter, State Key Laboratory of Structural Chemistry, The Graduate School of the Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Zhu X. Electronic states of Ga(3)Si, GaSi(3), and their ions. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:596-603. [PMID: 16257764 DOI: 10.1016/j.saa.2004.12.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2004] [Accepted: 12/15/2004] [Indexed: 05/05/2023]
Abstract
The equilibrium geometries and electronic states of Ga(3)Si, GaSi(3), and their ions are investigated using the complete active space self-consistent-field (CASSCF) and DFT(B3LYP)/CCSD(T) techniques. The (2)B(1), (3)B(1), and (1)A(1) states in C(2v) symmetry with a planar quadrilateral geometry are found to be the ground states of Ga(3)Si, Ga(3)Si(+), and Ga(3)Si(-), respectively. On the other hand, the ground states of GaSi(3), GaSi(3)(-) are also predicted to undergo Jahn-Teller distortion to the (2)A'' and (1)A' states in C(s) with a distorted triangular pyramid geometry, respectively, whereas that of GaSi(3)(+) is found to be the (1)A(1) state in C(3v) with symmetric triangular pyramid structure. Binding energies, electron affinities, ionization energies of Ga(3)Si and GaSi(3) are computed at the CCSD(T)/QCISD(T) level and discussed.
Collapse
Affiliation(s)
- Xiaolei Zhu
- Department of Chemistry, Nanjing Normal University, Nanjing 210097, PR China.
| |
Collapse
|
13
|
Zhu X. Spectroscopic properties of gallium arsenide tetramers: Ga2As2, Ga2As2+ and Ga2As2-. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 61:2730-6. [PMID: 16043071 DOI: 10.1016/j.saa.2004.10.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Accepted: 10/12/2004] [Indexed: 05/03/2023]
Abstract
Spectroscopic properties of the low-lying electronic states of Ga2As2 and its ions are studied using the complete active-space self-consistent field (CASSCF) and density function theory (DFT) followed by the coupled-cluster single and double substitutions (including triple excitations) (CCSD(T)) calculations. The stability of low-lying electronic states is examined by computing vibrational frequency. The energies of the ground states and a number of excited electronic states have been computed to predict the spectra of Ga2As2 and its ions. The ionization energy, electronic affinity, and atomization energy are estimated at the CCSD(T)/6-311+G(d) level and compared with the available experimental results.
Collapse
Affiliation(s)
- Xiaolei Zhu
- Department of Chemistry, Nanjing Normal University, Nanjing 210097, PR China; Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, PR China
| |
Collapse
|
14
|
Zhao Y, Xu W, Li Q, Xie Y, Schaefer HF. Gallium Clusters Gan (n = 1−6): Structures, Thermochemistry, and Electron Affinities. J Phys Chem A 2004. [DOI: 10.1021/jp0402784] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
15
|
Meloni G, Ferguson MJ, Sheehan SM, Gomez H, Liu Z, Neumark DM. Probing the connection between cluster and bulk electronic structure of InP using vacuum ultraviolet anion photoelectron spectroscopy. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.05.051] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
16
|
Costales A, Pandey R. A theoretical study of structural, vibrational, and electronic properties of neutral, positive, and negative indium arsenide clusters, (n=1,2,3). Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)01076-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
17
|
Kandalam AK, Blanco MA, Pandey R. Theoretical Study of AlnNn, GanNn, and InnNn (n = 4, 5, 6) Clusters. J Phys Chem B 2002. [DOI: 10.1021/jp0140062] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anil K. Kandalam
- Department of Physics, Michigan Technological University, Houghton, Michigan 49931
| | - Miguel A. Blanco
- Department of Physics, Michigan Technological University, Houghton, Michigan 49931
| | - Ravindra Pandey
- Department of Physics, Michigan Technological University, Houghton, Michigan 49931
| |
Collapse
|