1
|
Moreno N, Hadad CZ, Restrepo A. Microsolvation of electrons by a handful of ammonia molecules. J Chem Phys 2022; 157:134301. [PMID: 36209021 DOI: 10.1063/5.0107245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Microsolvation of electrons in ammonia is studied here via anionic NH3 n - clusters with n = 2-6. Intensive samplings of the corresponding configurational spaces using second-order perturbation theory with extended basis sets uncover rich and complex energy landscapes, heavily populated by many local minima in tight energy windows as calculated from highly correlated coupled cluster methods. There is a marked energetical preference for structures that place the excess electron external to the molecular frame, effectively coordinating it with the three protons from a single ammonia molecule. Overall, as the clusters grow in size, the lowest energy dimer serves as the basic motif over which additional ammonia molecules are attached via unusually strong charge-assisted hydrogen bonds. This is a priori quite unexpected because, on electrostatic grounds, the excess electron would be expected to be in contact with as many protons as possible. Accordingly, a full quantum mechanical treatment of the bonding interactions under the tools provided by the quantum theory of atoms in molecules is carried out in order to dissect and understand the nature of intermolecular contacts. Vertical detachment energies reveal bound electrons even for n = 2.
Collapse
Affiliation(s)
- Norberto Moreno
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Cacier Z Hadad
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Albeiro Restrepo
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| |
Collapse
|
2
|
Erukala S, Feinberg A, Singh A, Vilesov AF. Infrared spectroscopy of carbocations upon electron ionization of ethylene in helium nanodroplets. J Chem Phys 2021; 155:084306. [PMID: 34470362 DOI: 10.1063/5.0062171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electron impact ionization of helium droplets doped with ethylene molecules and clusters yields diverse CXHY + cations embedded in the droplets. The ionization primarily produces C2H2 +, C2H3 +, C2H4 +, and CH2 +, whereas larger carbocations are produced upon the reactions of the primary ions with ethylene molecules. The vibrational excitation of the cations leads to the release of bare cations and cations with a few helium atoms attached. The laser excitation spectra of the embedded cations show well resolved vibrational bands with a few wavenumber widths-an order of magnitude less than those previously obtained in solid matrices or molecular beams by tagging techniques. Comparison with the previous studies of free and tagged CH2 +, CH3 +, C2H2 +, C2H3 +, and C2H4 + cations shows that the helium matrix typically introduces a shift in the vibrational frequencies of less than about 20 cm-1, enabling direct comparisons with the results of quantum chemical calculations for structure determination. This work demonstrates a facile technique for the production and spectroscopic study of diverse carbocations, which act as important intermediates in gas and condensed phases.
Collapse
Affiliation(s)
- Swetha Erukala
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Alexandra Feinberg
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Amandeep Singh
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Andrey F Vilesov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| |
Collapse
|
3
|
Mi D, Cui J, Kuang S, Dong X, Lu H. Facile Atmospheric Generation of Water Radical Cations via
TiO
2
‐Nanoneedle Arrays for Aromatic Hydrocarbon Detection Based on Corona Discharge. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Dongbo Mi
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of Technology Nanchang 330013 China
| | - Jinhaojie Cui
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of Technology Nanchang 330013 China
| | - Siliang Kuang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry Jilin University Changchun 130012 China
| | - Xiaofeng Dong
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of Technology Nanchang 330013 China
| | - Haiyan Lu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry Jilin University Changchun 130012 China
| |
Collapse
|
4
|
Dasgupta S, Rana B, Herbert JM. Ab Initio Investigation of the Resonance Raman Spectrum of the Hydrated Electron. J Phys Chem B 2019; 123:8074-8085. [PMID: 31442044 DOI: 10.1021/acs.jpcb.9b04895] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
According to the conventional picture, the aqueous or "hydrated" electron, e-(aq), occupies an excluded volume (cavity) in the structure of liquid water. However, simulations with certain one-electron models predict a more delocalized spin density for the unpaired electron, with no distinct cavity structure. It has been suggested that only the latter (non-cavity) structure can explain the hydrated electron's resonance Raman spectrum, although this suggestion is based on calculations using empirical frequency maps developed for neat liquid water, not for e-(aq). All-electron ab initio calculations presented here demonstrate that both cavity and non-cavity models of e-(aq) afford significant red-shifts in the O-H stretching region. This effect is nonspecific and arises due to electron penetration into frontier orbitals of the water molecules. Only the conventional cavity model, however, reproduces the splitting of the H-O-D bend (in isotopically mixed water) that is observed experimentally and arises due to the asymmetric environments of the hydroxyl moieties in the electron's first solvation shell. We conclude that the cavity model of e-(aq) is more consistent with the measured resonance Raman spectrum than is the delocalized, non-cavity model, despite previous suggestions to the contrary. Furthermore, calculations with hybrid density functionals and with Hartree-Fock theory predict that non-cavity liquid geometries afford only unbound (continuum) states for an extra electron, whereas in reality this energy level should lie more than 3 eV below vacuum level. As such, the non-cavity model of e-(aq) appears to be inconsistent with available vibrational spectroscopy, photoelectron spectroscopy, and quantum chemistry.
Collapse
Affiliation(s)
- Saswata Dasgupta
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Bhaskar Rana
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - John M Herbert
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| |
Collapse
|
5
|
Zeng HJ, Yang N, Johnson MA. Introductory lecture: advances in ion spectroscopy: from astrophysics to biology. Faraday Discuss 2019; 217:8-33. [PMID: 31094388 DOI: 10.1039/c9fd00030e] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This introduction provides a historical context for the development of ion spectroscopy over the past half century by following the evolution of experimental methods to the present state-of-the-art. Rather than attempt a comprehensive review, we focus on how early work on small ions, carried out with fluorescence, direct absorption, and photoelectron spectroscopy, evolved into powerful technologies that can now address complex chemical problems ranging from catalysis to biophysics. One of these developments is the incorporation of cooling and temperature control to enable the general application of "messenger tagging" vibrational spectroscopy, first carried out using ionized supersonic jets and then with buffer gas cooling in radiofrequency ion traps. Some key advances in the application of time-resolved pump-probe techniques to follow ultrafast dynamics are also discussed, as are significant benchmarks in the refinement of ion mobility to allow spectroscopic investigation of large biopolymers with well-defined shapes. We close with a few remarks on challenges and opportunities to explore molecular level mechanics that drive macroscopic behavior.
Collapse
Affiliation(s)
- Helen J Zeng
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520, USA.
| | - Nan Yang
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520, USA.
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Yale University, New Haven, CT 06520, USA.
| |
Collapse
|
6
|
Abstract
A cavity or excluded-volume structure best explains the experimental properties of the aqueous or “hydrated” electron.
Collapse
Affiliation(s)
- John M. Herbert
- Department of Chemistry & Biochemistry
- The Ohio State University
- Columbus
- USA
| |
Collapse
|
7
|
Akhgarnusch A, Tang WK, Zhang H, Siu CK, Beyer MK. Charge transfer reactions between gas-phase hydrated electrons, molecular oxygen and carbon dioxide at temperatures of 80-300 K. Phys Chem Chem Phys 2016; 18:23528-37. [PMID: 27498686 DOI: 10.1039/c6cp03324e] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The recombination reactions of gas-phase hydrated electrons (H2O)n˙(-) with CO2 and O2, as well as the charge exchange reaction of CO2˙(-)(H2O)n with O2, were studied by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry in the temperature range T = 80-300 K. Comparison of the rate constants with collision models shows that CO2 reacts with 50% collision efficiency, while O2 reacts considerably slower. Nanocalorimetry yields internally consistent results for the three reactions. Converted to room temperature condensed phase, this yields hydration enthalpies of CO2˙(-) and O2˙(-), ΔHhyd(CO2˙(-)) = -334 ± 44 kJ mol(-1) and ΔHhyd(O2˙(-)) = -404 ± 28 kJ mol(-1). Quantum chemical calculations show that the charge exchange reaction proceeds via a CO4˙(-) intermediate, which is consistent with a fully ergodic reaction and also with the small efficiency. Ab initio molecular dynamics simulations corroborate this picture and indicate that the CO4˙(-) intermediate has a lifetime significantly above the ps regime.
Collapse
Affiliation(s)
- Amou Akhgarnusch
- Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, 24098 Kiel, Germany
| | | | | | | | | |
Collapse
|
8
|
DeBlase AF, Wolke CT, Weddle GH, Archer KA, Jordan KD, Kelly JT, Tschumper GS, Hammer NI, Johnson MA. Water network-mediated, electron-induced proton transfer in [C5H5N ⋅ (H2O)n](-) clusters. J Chem Phys 2016; 143:144305. [PMID: 26472377 DOI: 10.1063/1.4931928] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The role of proton-assisted charge accommodation in electron capture by a heterocyclic electron scavenger is investigated through theoretical analysis of the vibrational spectra of cold, gas phase [Py ⋅ (H2O)n=3-5](-) clusters. These radical anions are formed when an excess electron is attached to water clusters containing a single pyridine (Py) molecule in a supersonic jet ion source. Under these conditions, the cluster ion distribution starts promptly at n = 3, and the photoelectron spectra, combined with vibrational predissociation spectra of the Ar-tagged anions, establish that for n > 3, these species are best described as hydrated hydroxide ions with the neutral pyridinium radical, PyH((0)), occupying one of the primary solvation sites of the OH(-). The n = 3 cluster appears to be a special case where charge localization on Py and hydroxide is nearly isoenergetic, and the nature of this species is explored with ab initio molecular dynamics calculations of the trajectories that start from metastable arrangements of the anion based on a diffuse, essentially dipole-bound electron. These calculations indicate that the reaction proceeds via a relatively slow rearrangement of the water network to create a favorable hydration configuration around the water molecule that eventually donates a proton to the Py nitrogen atom to yield the product hydroxide ion. The correlation between the degree of excess charge localization and the evolving shape of the water network revealed by this approach thus provides a microscopic picture of the "solvent coordinate" at the heart of a prototypical proton-coupled electron transfer reaction.
Collapse
Affiliation(s)
- Andrew F DeBlase
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
| | - Conrad T Wolke
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
| | - Gary H Weddle
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
| | - Kaye A Archer
- Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, USA
| | - Kenneth D Jordan
- Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, USA
| | - John T Kelly
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, USA
| | - Gregory S Tschumper
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, USA
| | - Nathan I Hammer
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, USA
| | - Mark A Johnson
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
| |
Collapse
|
9
|
Gong ZY, Duan S, Tian G, Jiang J, Xu X, Luo Y. Infrared spectra of small anionic water clusters from density functional theory and wavefunction theory calculations. Phys Chem Chem Phys 2015; 17:12698-707. [PMID: 25903989 DOI: 10.1039/c5cp01378j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We performed systematic theoretical studies on small anionic water/deuterated water clusters W/D(-)(N=2-6) at both density functional theory (B3LYP) and wavefunction theory (MP2) levels. The focus of the study is to examine the convergence of calculated infrared (IR) spectra with respect to the increasing number of diffuse functions. It is found that at the MP2 level for larger clusters (n = 4-6), only one extra diffuse function is needed to obtain the converged relative IR intensities, while two or three more sets of extra diffuse functions are needed for smaller clusters. Such behaviour is strongly associated with the convergence of the electronic structure of corresponding clusters at the MP2 level. It is striking to observe that at the B3LYP level, the calculated relative IR intensities for all the clusters under investigations are diverse and show no trend of convergence upon increasing the number of diffuse functions. Moreover, the increasing contribution from the extra diffuse functions to the dynamic IR dipole moment indicates that the B3LYP electronic structure also fails to converge. These results manifest that MP2 is a preferential theoretical method, as compared to the widely used B3LYP, for the IR intensity of dipole bounded electron systems.
Collapse
Affiliation(s)
- Zu-Yong Gong
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | | | | | | | | | | |
Collapse
|
10
|
Huang DL, Liu HT, Ning CG, Wang LS. Vibrational state-selective autodetachment photoelectron spectroscopy from dipole-bound states of cold 2-hydroxyphenoxide: o − HO(C6H4)O−. J Chem Phys 2015; 142:124309. [DOI: 10.1063/1.4916122] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Dao-Ling Huang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Hong-Tao Liu
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Chuan-Gang Ning
- Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| |
Collapse
|
11
|
Prell JS, Chang TM, Biles JA, Berden G, Oomens J, Williams ER. Isomer Population Analysis of Gaseous Ions From Infrared Multiple Photon Dissociation Kinetics. J Phys Chem A 2011; 115:2745-51. [DOI: 10.1021/jp2004166] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- James S. Prell
- Department of Chemistry, University of California, Berkeley, California 94720-1460, United States
| | - Terrence M. Chang
- Department of Chemistry, University of California, Berkeley, California 94720-1460, United States
| | - Jeffrey A. Biles
- Department of Chemistry, University of California, Berkeley, California 94720-1460, United States
| | - Giel Berden
- FOM Institute for Plasma Physics Rijnhuizen, Edisonbaan 14, 3439 MN Nieuwegein, The Netherlands
| | - Jos Oomens
- FOM Institute for Plasma Physics Rijnhuizen, Edisonbaan 14, 3439 MN Nieuwegein, The Netherlands
- University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
| | - Evan R. Williams
- Department of Chemistry, University of California, Berkeley, California 94720-1460, United States
| |
Collapse
|
12
|
Herbert JM, Jacobson LD. Nature's most squishy ion: The important role of solvent polarization in the description of the hydrated electron. INT REV PHYS CHEM 2011. [DOI: 10.1080/0144235x.2010.535342] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
13
|
Duncan MA. Infrared spectroscopy to probe structure and dynamics in metal ion-molecule complexes. INT REV PHYS CHEM 2010. [DOI: 10.1080/0144235031000095201] [Citation(s) in RCA: 280] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Michael A. Duncan
- a Department of Chemistry , University of Georgia , Athens , GA , 30602-2556 , USA
| |
Collapse
|
14
|
Wild DA, Bieske EJ. Infrared Investigations of Negatively Charged Complexes and Clusters. INT REV PHYS CHEM 2010. [DOI: 10.1080/0144235021000060165] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- D. A. Wild
- a School of Chemistry , University of Melbourne , Parkville , Victoria , 3010 , Australia
| | - E. J. Bieske
- a School of Chemistry , University of Melbourne , Parkville , Victoria , 3010 , Australia
| |
Collapse
|
15
|
Beck JP, Lisy JM. Cooperatively Enhanced Ionic Hydrogen Bonds in Cl−(CH3OH)1−3Ar Clusters. J Phys Chem A 2010; 114:10011-5. [DOI: 10.1021/jp105555p] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jordan P. Beck
- Department of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
| | - James M. Lisy
- Department of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
| |
Collapse
|
16
|
Prell JS, O'Brien JT, Williams ER. IRPD spectroscopy and ensemble measurements: effects of different data acquisition and analysis methods. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:800-9. [PMID: 20185332 DOI: 10.1016/j.jasms.2010.01.010] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 01/06/2010] [Accepted: 01/10/2010] [Indexed: 05/17/2023]
Abstract
Three different commonly used infrared photodissociation (IRPD) spectroscopy acquisition and analysis methods are described, and results from these methods are compared using the same dataset for an extensively hydrated metal cation, La(3+)(H(2)O)(36). Using the first-order laser-induced photodissociation rate constant as an IRPD intensity has several advantages over photodissociation yield and depletion/appearance methods in that intensities can be more directly compared with calculated infrared absorption spectra, and the intensities can be readily corrected for changes in laser power or irradiation times used for optimum data acquisition at each frequency. Extending IRPD spectroscopy to large clusters can be complicated when blackbody infrared radiative dissociation competes strongly with laser-induced photodissociation. A new method to obtain IRPD spectra of single precursor ions or ensembles of precursor ions that is nearly equivalent to the photodissociation rate constant method for single precursor ions is demonstrated. The ensemble IRPD spectra represent the "average" structure of clusters of a given size range, and this method has the advantage that spectra with improved signal-to-noise ratios can be obtained with no increase in data acquisition time. Results using this new method for a precursor ensemble consisting of La(3+)(H(2)O)(35-37) are compared with results for La(3+)(H(2)O)(36).
Collapse
Affiliation(s)
- James S Prell
- Department of Chemistry, University of California, Berkeley, California 94720-1460, USA
| | | | | |
Collapse
|
17
|
Novakovskaya YV. Cluster anions: Nonempirical estimate of the electron hydration energy. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2010. [DOI: 10.1134/s0036024410020159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
18
|
Steill JD, Oomens J. Action Spectroscopy of Gas-Phase Carboxylate Anions by Multiple Photon IR Electron Detachment/Attachment. J Phys Chem A 2009; 113:4941-6. [DOI: 10.1021/jp807710y] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Jeffrey D. Steill
- FOM Institute for Plasma Physics ‘Rijnhuizen’, Edisonbaan 14, 3439MN Nieuwegein, The Netherlands
| | - Jos Oomens
- FOM Institute for Plasma Physics ‘Rijnhuizen’, Edisonbaan 14, 3439MN Nieuwegein, The Netherlands
| |
Collapse
|
19
|
Photoelectron imaging study of vibrationally mediated electron autodetachment in the type I isomer of the water hexamer anion. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.11.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
20
|
|
21
|
Schneider H, Vogelhuber KM, Schinle F, Stanton JF, Weber JM. Vibrational Spectroscopy of Nitroalkane Chains Using Electron Autodetachment and Ar Predissociation. J Phys Chem A 2008; 112:7498-506. [DOI: 10.1021/jp800124s] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Holger Schneider
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - Kristen M. Vogelhuber
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - Florian Schinle
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - John F. Stanton
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - J. Mathias Weber
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| |
Collapse
|
22
|
Spectroscopy of the Potential Energy Surfaces for CH and CO Bond Activation by Transition Metal and Metal Oxide Cations. ADVANCES IN CHEMICAL PHYSICS 2008. [DOI: 10.1002/9780470259474.ch6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
|
23
|
|
24
|
Singh NJ, Lee EC, Choi YC, Lee HM, Kim KS. Understanding Clusters toward the Design of Functional Molecules and Nanomaterials. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2007. [DOI: 10.1246/bcsj.80.1437] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
25
|
Abstract
The M+[cyclohexane][Ar] (M = Li, Na, and K) cluster ions were investigated using infrared photodissociation spectroscopy in the C-H stretching region. The alkali metal cation binds to the cyclohexane ring above the ring on the S6 axis via eta3 coordination. The C-H stretching modes are perturbed due to binding of the metal cation and display a significant spread in frequency. The shifts are greatest for the Li+ and decrease for Na+ and K+ with increasing ionic radius. It has been observed that cyclohexane displays greater selectivity for Li+ over Na+ than the cyclic ether, 12-crown-4. The charge transfer interaction between Li+ and cyclohexane is believed to be responsible for the selectivity of Li+ over other alkali metal ions.
Collapse
Affiliation(s)
- G Naresh Patwari
- Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, Illinois 61801, USA.
| | | |
Collapse
|
26
|
Walker NR, Walters RS, Tsai MK, Jordan KD, Duncan MA. Infrared photodissociation spectroscopy of Mg(+)(H2O)Ar(n) complexes: isomers in progressive microsolvation. J Phys Chem A 2007; 109:7057-67. [PMID: 16834068 DOI: 10.1021/jp051877t] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ion-molecule complexes of the form Mg(H2O)Ar(n)+ (n = 1-8) are produced by laser vaporization in a pulsed-nozzle cluster source. These complexes are mass-selected and studied with infrared photodissociation spectroscopy in the O-H stretch region. The spectra are interpreted with the aid of ab initio calculations on the n = 1-5 complexes, including examination of various isomeric structures. The combined spectroscopic and theoretical studies reveal the presence of multiple isomeric structures at each cluster size, as the argon atoms assemble around the Mg(+)(H2O) unit. Distinct infrared resonances are measured for argon-on-metal, argon-on-OH and argon-on-two-OH isomers.
Collapse
Affiliation(s)
- N R Walker
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA
| | | | | | | | | |
Collapse
|
27
|
Jaeger JB, Pillai ED, Jaeger TD, Duncan MA. Ultraviolet and infrared photodissociation of Si(+)(C6H6)n and Si(+)(C6H6)(n)Ar clusters. J Phys Chem A 2007; 109:2801-8. [PMID: 16833593 DOI: 10.1021/jp044798a] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Ion-molecule complexes of the form Si(+)(C6H6)n and Si(+)(C6H6)(n)Ar are produced by laser vaporization in a pulsed nozzle cluster source. These clusters are mass-selected and studied with ultraviolet (355 nm) photodissociation and resonance-enhanced infrared photodissociation spectroscopy in the C-H stretch region of benzene. In the UV, Si(+)(C6H6)n clusters (n = 1-5) fragment to produce the Si(+)(C6H6)n mono-ligand species, suggesting that this ion has enhanced relative stability. IR photodissociation of Si(+)(C6H6)n complexes occurs by the elimination of benzene, while Si(+)(C6H6)(n)Ar complexes lose Ar. Resonances reveal C-H vibrational bands in the 2900-3300 cm(-1) region characteristic of the benzene ligand with shifts caused by the silicon cation bonding. The IR spectra confirm that the major component of the Si(+)(C6H6)n ions studied have the pi-complex structure rather than the isomeric insertion products suggested previously.
Collapse
Affiliation(s)
- J B Jaeger
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA
| | | | | | | |
Collapse
|
28
|
Abstract
Clusters of atoms/molecules show dynamics characteristic of the method of excitation. Two contrasted processes are discussed: (1) electronic excitation via single-photon absorption and (2) impulsive excitation of nuclear motions by surface impact. Process 1 is exemplified by photodissociation dynamics of size-selected metal cluster ions. The electronic energy is converted most likely to vibrational energy of internal modes; dissociation follows via statistical mechanism to produce energetically favored fragments. Exceptionally, a silver cluster ion, Ag4(+), is shown to undergo nonstatistical dissociation along the potential-energy surface of the excited state. Energy partitioning to translational and vibrational modes of fragments is analyzed as well as bond dissociation energies. Furthermore, the spectrum of the photodissociation yield provides electronic and geometrical structures of a cluster with the aid of ab initio calculations; manganese, Mn(N)(+), and chromium, Cr(N)(+), cluster ions are discussed, where the importance of magnetic interactions is manifested. On the other hand, momentum transfer upon surface impact plays a role in process 2. An impulsive mechanical force triggers extraordinary chemical processes distinct from those initiated by atomic collision as well as photoexcitation. Experiments on aluminum, Al(N)(-), silicon, SiN(-), and solvated, I(2)(-)(CO2)(N), cluster anions provide evidence for reactions proceeding under extremely high temperatures, such as pickup of surface atoms, annealing of products, and mechanical splitting of chemical bonds. In addition, a model experiment to visualize and time-resolve the cluster impact process is performed by using a micrometer-sized liquid droplet. Multiphoton absorption initiates superheating of the droplet surface followed by a shock wave and disintegration into a number of small fragments (shattering). These studies further reveal how the nature of chemical bonds influences the dynamics of clusters.
Collapse
Affiliation(s)
- Akira Terasaki
- Cluster Research Laboratory, Toyota Technological Institute, in East Tokyo Laboratory, Genesis Research Institute, Inc., 717-86 Futamata, Ichikawa, Chiba 272-0001, Japan.
| |
Collapse
|
29
|
Asmis KR, Santambrogio G, Zhou J, Garand E, Headrick J, Goebbert D, Johnson MA, Neumark DM. Vibrational spectroscopy of hydrated electron clusters(H2O)15–50− via infrared multiple photon dissociation. J Chem Phys 2007; 126:191105. [PMID: 17523785 DOI: 10.1063/1.2741508] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Infrared multiple photon dissociation spectra for size-selected water cluster anions (H2O)(n)(-), n=15-50, are presented covering the frequency range of 560-1820 cm(-1). The cluster ions are trapped and cooled by collisions with ambient He gas at 20 K, with the goal of defining the cluster temperature better than in previous investigations of these species. Signal is seen in two frequency regions centered around 700 and 1500-1650 cm(-1), corresponding to water librational and bending motions, respectively. The bending feature associated with a double-acceptor water molecule binding to the excess electron is clearly seen up to n=35, but above n=25; this feature begins to blueshift and broadens, suggesting a more delocalized electron binding motif for the larger clusters in which the excess electron interacts with multiple water molecules.
Collapse
Affiliation(s)
- Knut R Asmis
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Metz RB. Photofragment spectroscopy of covalently bound transition metal complexes: a window into C–H and C–C bond activation by transition metal ions. INT REV PHYS CHEM 2007. [DOI: 10.1080/01442350310001654065] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Ricardo B. Metz
- a Department of Chemistry , University of Massachusetts , Amherst, MA 01003, USA
| |
Collapse
|
31
|
Sobolewski AL, Domcke W. Computational studies of aqueous-phase photochemistry and the hydrated electron in finite-size clusters. Phys Chem Chem Phys 2007; 9:3818-29. [PMID: 17637974 DOI: 10.1039/b704066k] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A survey of recent ab initio calculations on excited electronic states of water clusters and various chromophore-water clusters is given. Electron and proton transfer processes in these systems have been characterized by the determination of electronic wave functions, minimum-energy reaction paths and potential-energy profiles. It is pointed out that the transfer of a neutral hydrogen atom (leading to biradicals) rather than the transfer of a proton (leading to ion pairs) is the generic excited-state reaction mechanism in these systems. The hydrated hydronium radical, (H3O)(aq), plays a central role in this scenario. The electronic and vibrational spectra of H3O(H2O)(n) clusters and the decay mechanism of these metastable species have been investigated in some detail. The results suggest that (H3O)(aq) could be the carrier of the characteristic spectroscopic properties of the hydrated electron in liquid water.
Collapse
|
32
|
Abstract
Experiments are reviewed in which key problems in chemical dynamics are probed by experiments based on photodetachment and/or photoexcitation of negative ions. Examples include transition state spectroscopy of biomolecular reactions, spectroscopy of open shell van der Waals complexes, photodissociation of free radicals, and time-resolved dynamics in clusters. The experimental methods used in these investigations are described along with representative systems that have been studied.
Collapse
Affiliation(s)
- Daniel M Neumark
- Department of Chemistry,University of California, Berkeley, California 94720, USA.
| |
Collapse
|
33
|
Herbert JM, Head-Gordon M. Charge Penetration and the Origin of Large O−H Vibrational Red-Shifts in Hydrated-Electron Clusters, (H2O)n-. J Am Chem Soc 2006; 128:13932-9. [PMID: 17044721 DOI: 10.1021/ja064949i] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The origin of O-H vibrational red-shifts observed experimentally in (H2O)n(-) clusters is analyzed using electronic structure calculations, including natural bond orbital analysis. The red-shifts are shown to arise from significant charge transfer and strong donor-acceptor stabilization between the unpaired electron and O-H sigma* orbitals on a nearby water molecule in a double hydrogen-bond-acceptor ("AA") configuration. The extent of e(-) --> sigma* charge transfer is comparable to the n --> sigma* charge transfer in the most strongly hydrogen-bonded X(-)(H2O) complexes (e.g., X = F, O, OH), even though the latter systems exhibit much larger vibrational red-shifts. In X(-)(H2O), the proton affinity of X(-) induces a low-energy XH...(-)OH diabatic state that becomes accessible in v = 1 of the shared-proton stretch, leading to substantial anharmonicity in this mode. In contrast, the H + (-)OH(H2O)(n-1) diabat of (H2O)n(-) is not energetically accessible; thus, the O-H stretching modes of the AA water are reasonably harmonic, and their red-shifts are less dramatic. Only a small amount of charge penetrates beyond the AA water molecule, even upon vibrational excitation of these AA modes. Implications for modeling of the aqueous electron are discussed.
Collapse
Affiliation(s)
- John M Herbert
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | | |
Collapse
|
34
|
Herbert JM, Head-Gordon M. First-principles, quantum-mechanical simulations of electron solvation by a water cluster. Proc Natl Acad Sci U S A 2006; 103:14282-7. [PMID: 16973747 PMCID: PMC1599955 DOI: 10.1073/pnas.0603679103] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Indexed: 11/18/2022] Open
Abstract
Despite numerous experiments and static electronic structure calculations, the nature of hydrated-electron clusters, (H2O)(n)(-), remains poorly understood. Here, we introduce a hybrid ab initio molecular dynamics scheme, balancing accuracy against feasibility, to simulate vibrational and photoelectron spectra of (H(2)O)(n)(-), treating all electrons quantum-mechanically. This methodology provides a computational tool for understanding the spectra of weakly bound and supramolecular anions and for elucidating the fingerprint of dynamics in these spectra. Simulations of (H2O)(4)(-) provide quantitative agreement with experimental spectra and furnish direct evidence of the nonequilibrium nature of the cluster ensemble that is probed experimentally. The simulations also provide an estimate of the cluster temperature (T approximately 150-200 K) that is not available from experiment alone. The "double acceptor" electron-binding motif is found to be highly stable with respect to thermal fluctuations, even at T = 300 K, whereas the extra electron stabilizes what would otherwise be unfavorable water configurations.
Collapse
Affiliation(s)
- John M Herbert
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
| | | |
Collapse
|
35
|
Walters RS, Pillai ED, Duncan MA. Solvation dynamics in Ni+ (H2O)n clusters probed with infrared spectroscopy. J Am Chem Soc 2006; 127:16599-610. [PMID: 16305249 DOI: 10.1021/ja0542587] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Infrared photodissociation spectroscopy is reported for mass-selected Ni+ (H2O)n complexes in the O-H stretching region up to cluster sizes of n = 25. These clusters fragment by the loss of one or more intact water molecules, and their excitation spectra show distinct bands in the region of the symmetric and asymmetric stretches of water. The first evidence for hydrogen bonding, indicated by a broad band strongly red-shifted from the free OH region, appears at the cluster size of n = 4. At larger cluster sizes, additional red-shifted structure evolves over a broader wavelength range in the hydrogen-bonding region. In the free OH region, the symmetric stretch gradually diminishes in intensity, while the asymmetric stretch develops into a closely spaced doublet near 3700 cm(-1). The data indicate that essentially all of the water molecules are in a hydrogen-bonded network by the size of n = 10. However, there is no evidence for the formation of clathrate structures seen recently via IR spectroscopy of protonated water clusters.
Collapse
Affiliation(s)
- Richard S Walters
- Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA
| | | | | |
Collapse
|
36
|
Walters RS, Pillai ED, Schleyer PVR, Duncan MA. Vibrational Spectroscopy and Structures of Ni+(C2H2)n (n =1−4) Complexes. J Am Chem Soc 2005; 127:17030-42. [PMID: 16316250 DOI: 10.1021/ja054800r] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nickel cation-acetylene complexes of the form Ni(+)(C(2)H(2))(n), Ni(+)(C(2)H(2))Ne, and Ni(+)(C(2)H(2))(n)Ar(m) (n = 1-4) are produced in a molecular beam by pulsed laser vaporization. These ions are size-selected and studied in a time-of-flight mass spectrometer by infrared laser photodissociation spectroscopy in the C-H stretch region. The fragmentation patterns indicate that the coordination number is 4 for this system. The n = 1-4 complexes with and without rare gas atoms are also investigated with density functional theory. The combined IR spectra and theory show that pi-complexes are formed for the n = 1-4 species, causing the C-H stretches in the acetylene ligands to shift to lower frequencies. Theory reveals that there are low-lying excited states nearly degenerate with the ground state for all the Ni(+)(C(2)H(2))(n) complexes. Although isomeric structures are identified for rare gas atom binding at different sites, the attachment of rare gas atoms results in only minor perturbations on the structures and spectra for all complexes. Experiment and theory agree that multiple acetylene binding takes place to form low-symmetry structures, presumably due to Jahn-Teller distortion and/or ligand steric effects. The fully coordinated Ni(+)(C(2)H(2))(4) complex has a near-tetrahedral structure.
Collapse
Affiliation(s)
- Richard S Walters
- Department of Chemistry, University of Georgia, Athens, 30602-2556, USA
| | | | | | | |
Collapse
|
37
|
Hammer NI, Roscioli JR, Johnson MA, Myshakin EM, Jordan KD. Infrared Spectrum and Structural Assignment of the Water Trimer Anion. J Phys Chem A 2005; 109:11526-30. [PMID: 16354044 DOI: 10.1021/jp053769c] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The bending vibrational spectrum of the perdeutero isotopomer of the water trimer anion has been measured and compared with spectra calculated using the MP2, CCSD, and Becke3LYP electronic structure methods. Due to its low electron binding energy (approximately 150 meV), only the OD bending region of the IR spectrum of (D2O)3(-) is accessible experimentally, with electron ejection dominating at higher photon energies. The calculated spectrum of the isomer having three water molecules arranged in a chain agrees best with the experimental spectrum. In the chain isomer, the excess electron is bound to the terminal water monomer with two dangling OH groups. This is consistent with the electron binding mechanism established previously for the (H2O)n(-) (n = 2, 4-6) anions.
Collapse
Affiliation(s)
- N I Hammer
- Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
| | | | | | | | | |
Collapse
|
38
|
Abstract
Ab initio electronic structure calculations have been performed for (CH(3)CN)(2) (-) and (CH(3)CN)(3) (-) cluster anions using a diffuse basis set. We found both the dipole-bound structures and internal structures, where in the former structure an excess electron is mainly distributed on the surface of the cluster while an excess electron is internally trapped in the latter configuration. The optimized structures found for cluster anions were compared to those for neutral clusters. Potential-energy surfaces were also plotted as a function of appropriate internal coordinates in order to understand the interconversions of the optimized structures of clusters. The relative stabilities of the optimized confirmers have been discussed on the basis of the characteristics of these potential surfaces, relative energies, and electron vertical detachment energies.
Collapse
|
39
|
Herbert JM, Head-Gordon M. Calculation of Electron Detachment Energies for Water Cluster Anions: An Appraisal of Electronic Structure Methods, with Application to (H2O)20- and (H2O)24-. J Phys Chem A 2005; 109:5217-29. [PMID: 16833879 DOI: 10.1021/jp051096s] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We present benchmark calculations of vertical electron detachment energies (VDEs) for various conformers of (H2O)n-, using both wave function and density functional methods, in sequences of increasingly diffuse Gaussian basis sets. For small clusters (n < or = 6), a systematic examination of VDE convergence reveals that it is possible to converge this quantity to within approximately 0.01 eV of the complete-basis limit, using a highly diffuse but otherwise economical Pople-style basis set of double-zeta quality, with 28 atom-centered basis functions per water molecule. Floating-center basis functions can be useful but are not required to obtain accurate VDEs. Second-order Møller-Plesset perturbation (MP2) theory suffices to obtain VDEs that are within 0.05 eV of the results from both experiment and coupled-cluster theory, and which always err toward underbinding the extra electron. In contrast to these consistent predictions, VDEs calculated using density functional theory (DFT) vary widely, according to the fraction of Hartree-Fock exchange in a given functional. Common functionals such as BLYP and B3LYP overestimate the VDE by 0.2-0.5 eV, whereas a variant of Becke's "half and half" functional is much closer to coupled-cluster predictions. Exploratory calculations for (H2O)20- and (H2O)24- cast considerable doubt on earlier calculations that were used to assign the photoelectron spectra of these species to particular cluster isomers.
Collapse
Affiliation(s)
- John M Herbert
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | | |
Collapse
|
40
|
Hammer NI, Shin JW, Headrick JM, Diken EG, Roscioli JR, Weddle GH, Johnson MA. How do small water clusters bind an excess electron? Science 2004; 306:675-9. [PMID: 15375220 DOI: 10.1126/science.1102792] [Citation(s) in RCA: 234] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The arrangement of water molecules around a hydrated electron has eluded explanation for more than 40 years. Here we report sharp vibrational bands for small gas-phase water cluster anions, (H2O)(4-6)- and (D2O)(4-6)-. Analysis of these bands reveals a detailed picture of the diffuse electron-binding site. The electron is closely associated with a single water molecule attached to the supporting network through a double H-bond acceptor motif. The local OH stretching bands of this molecule are dramatically distorted in the pentamer and smaller clusters because the excited vibrational levels are strongly coupled to the electron continuum. The vibration-to-electronic energy transfer rates, as revealed by line shape analysis, are mode-specific and remarkably fast, with the symmetric stretching mode surviving for less than 10 vibrational periods [50 fs in (H2O)4-].
Collapse
Affiliation(s)
- Nathan I Hammer
- Sterling Chemistry Laboratory, Yale University, Post Office Box 208107, New Haven, CT 06520, USA
| | | | | | | | | | | | | |
Collapse
|
41
|
Lee HM, Tarkeshwar P, Kim KS. Structures, energetics, and spectra of hydrated hydroxide anion clusters. J Chem Phys 2004; 121:4657-64. [PMID: 15332897 DOI: 10.1063/1.1779566] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The structures, energetics, electronic properties, and spectra of hydrated hydroxide anions are studied using density functional and high level ab initio calculations. The overall structures and binding energies are similar to the hydrated anion clusters, in particular, to the hydrated fluoride anion clusters except for the tetrahydrated clusters and hexahydrated clusters. In tetrahydrated system, tricoordinated structures and tetracoordinated structures are compatible, while in pentahydrated systems and hexahydrated systems, tetracoordinated structures are stable. The hexahydrated system is similar in structure to the hydrated chloride cluster. The thermodynamic quantities (enthalpies and free energies) of the clusters are in good agreement with the experimental values. The electronic properties induced by hydration are similar to hydrated chloride anions. The charge-transfer-to-solvent energies of these hydrated-hydroxide anions are discussed, and the predicted ir spectra are used to explain the experimental data in terms of the cluster structures. The low-energy barriers between the conformations along potential energy surfaces are reported.
Collapse
Affiliation(s)
- Han Myoung Lee
- National Creative Research Initiative Center for Superfunctional Materials, Department of Chemistry, Division of Molecular and Life Sciences, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea.
| | | | | |
Collapse
|
42
|
Vaden TD, Weinheimer CJ, Lisy JM. Evaporatively cooled M+(H2O)Ar cluster ions: Infrared spectroscopy and internal energy simulations. J Chem Phys 2004; 121:3102-7. [PMID: 15291620 DOI: 10.1063/1.1774157] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Rotationally resolved IR spectra of M+ (H2O)Ar cluster ions for M=Na, K, and Cs in the O-H stretch region were measured in a triple-quadrupole mass spectrometer. Analysis of the spectra yields O-H stretch vibrational band origins and relative IR intensities of the symmetric and asymmetric modes. The effect of the alkali-metal ions on these modes results in frequency shifts and intensity changes from the gas phase values of water. The A-rotational constants are also obtained from the rotational structure and are discussed. Experimentally, the temperatures of these species were deduced from the relative populations of the K-rotational states. The internal energies and temperatures of the cluster ions for Na and K were simulated using RRKM calculations and the evaporative ensemble formalism. With binding energies and vibrational frequencies obtained from ab initio calculations, the average predicted temperatures are qualitatively consistent with the experimental values and demonstrate the additional cooling resulting from argon evaporation.
Collapse
Affiliation(s)
- Timothy D Vaden
- Department of Chemistry, University of Illinois at Urbana-Champaign, 61801, USA
| | | | | |
Collapse
|
43
|
Myshakin EM, Diri K, Jordan KD. Theoretical Investigation of the Neutral Precursor of (H2O)6-. J Phys Chem A 2004. [DOI: 10.1021/jp048726v] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Evgeniy M. Myshakin
- Department of Chemistry and Center for Molecular and Materials Simulations, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Kadir Diri
- Department of Chemistry and Center for Molecular and Materials Simulations, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Kenneth D. Jordan
- Department of Chemistry and Center for Molecular and Materials Simulations, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| |
Collapse
|
44
|
|
45
|
Diken EG, Robertson WH, Johnson MA. The Vibrational Spectrum of the Neutral (H2O)6 Precursor to the “Magic” (H2O)6- Cluster Anion by Argon-Mediated, Population-Modulated Electron Attachment Spectroscopy. J Phys Chem A 2003. [DOI: 10.1021/jp0309973] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Eric G. Diken
- Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
| | - William H. Robertson
- Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
| | - Mark A. Johnson
- Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
| |
Collapse
|
46
|
Wang F, Jordan KD. Parallel-tempering Monte Carlo simulations of the finite temperature behavior of (H2O)6−. J Chem Phys 2003. [DOI: 10.1063/1.1624597] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
|
47
|
Theoretical Study of the Lowest Energy Structure of the Water Undecamer. B KOREAN CHEM SOC 2003. [DOI: 10.5012/bkcs.2003.24.6.777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
48
|
|
49
|
Zhan CG, Dixon DA. The Nature and Absolute Hydration Free Energy of the Solvated Electron in Water. J Phys Chem B 2003. [DOI: 10.1021/jp022326v] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chang-Guo Zhan
- William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, MS K1-83, P.O. Box 999, Richland, Washington 99352
| | - David A. Dixon
- William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, MS K1-83, P.O. Box 999, Richland, Washington 99352
| |
Collapse
|
50
|
Abstract
This review provides a historical context for our understanding of the hydration shell surrounding halide ions and illustrates how the cluster systems can be used, in combination with theory, to elucidate the behavior of water molecules in direct contact with the anion. We discuss how vibrational predissociation spectroscopy, carried out with weakly bound argon atoms, has been employed to deduce the morphology of the small water networks attached to anions in the primary steps of hydration. We emphasize the importance of charge-transfer in the binary interaction, and discuss how this process affects the structures of the larger networks. Finally, we survey how the negatively charged water clusters (H2O)n(-) are providing a molecular-level perspective on how diffuse excess electrons interact with the water networks.
Collapse
Affiliation(s)
- William H Robertson
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, P.O. Box 208107, New Haven, CT 06520, USA.
| | | |
Collapse
|