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On the structure of the matrix isolated water trimer.

Ceponkus, J ; Uvdal, Per LU and Nelander, Bengt LU (2011) In Journal of Chemical Physics 134(6).
Abstract
Infrared spectra of partially deuterated water trimers have been investigated. It is found that HDO(H(2)O)(2) has a single, bound OD stretching fundamental, (HDO)(2)H(2)O two bound OD stretches. (HDO)(3) has a single, bound OD stretch and (H(2)O)(3) has a pair of bound OH stretches. Ab initio and discrete Fourier transform (DFT) calculations predict that the water trimer has C(1) symmetry with six different, isoenergetic minima. These calculations consequently give three numerically different OD stretches for HDO(H(2)O)(2), six for (HDO)(2)H(2)O, three for (HDO)(3), and three bound OH stretches for (H(2)O)(3). The connection between the observations and the pseudorotation of the trimer is discussed with the help of Wales' pseudorotation... (More)
Infrared spectra of partially deuterated water trimers have been investigated. It is found that HDO(H(2)O)(2) has a single, bound OD stretching fundamental, (HDO)(2)H(2)O two bound OD stretches. (HDO)(3) has a single, bound OD stretch and (H(2)O)(3) has a pair of bound OH stretches. Ab initio and discrete Fourier transform (DFT) calculations predict that the water trimer has C(1) symmetry with six different, isoenergetic minima. These calculations consequently give three numerically different OD stretches for HDO(H(2)O)(2), six for (HDO)(2)H(2)O, three for (HDO)(3), and three bound OH stretches for (H(2)O)(3). The connection between the observations and the pseudorotation of the trimer is discussed with the help of Wales' pseudorotation model. It is found that pseudorotation is sufficiently fast to average the effective symmetry of the A(3) trimer to C(3h) and to eliminate the difference between the different ab initio minima for A(2)B. The only exception is (H(2)O)(3) where the splitting between the different bound OH stretches is largest. Here a doublet is observed due to incomplete averaging. DFT calculations indicate that the D-bonded form of HDO(H(2)O)(2) is between 50 and 60 cm(-1) more stable than the H-bonded form. The energy difference is determined by differences in zero point vibration energy of intermolecular librations of the two forms. Attempts to measure the energy difference indicate that the energy difference is larger, of the order of 100 cm(-1). (Less)
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type
Contribution to journal
publication status
published
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in
Journal of Chemical Physics
volume
134
issue
6
article number
064309
publisher
American Institute of Physics (AIP)
external identifiers
  • wos:000287327400029
  • pmid:21322682
  • scopus:79951787856
  • pmid:21322682
ISSN
0021-9606
DOI
10.1063/1.3551622
language
English
LU publication?
yes
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The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Max-laboratory (011012005), Chemical Physics (S) (011001060)
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847d48ce-673d-4461-bedf-8379c28b7e96 (old id 1831820)
date added to LUP
2016-04-01 10:00:46
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2021-09-29 05:04:05
@article{847d48ce-673d-4461-bedf-8379c28b7e96,
  abstract     = {Infrared spectra of partially deuterated water trimers have been investigated. It is found that HDO(H(2)O)(2) has a single, bound OD stretching fundamental, (HDO)(2)H(2)O two bound OD stretches. (HDO)(3) has a single, bound OD stretch and (H(2)O)(3) has a pair of bound OH stretches. Ab initio and discrete Fourier transform (DFT) calculations predict that the water trimer has C(1) symmetry with six different, isoenergetic minima. These calculations consequently give three numerically different OD stretches for HDO(H(2)O)(2), six for (HDO)(2)H(2)O, three for (HDO)(3), and three bound OH stretches for (H(2)O)(3). The connection between the observations and the pseudorotation of the trimer is discussed with the help of Wales' pseudorotation model. It is found that pseudorotation is sufficiently fast to average the effective symmetry of the A(3) trimer to C(3h) and to eliminate the difference between the different ab initio minima for A(2)B. The only exception is (H(2)O)(3) where the splitting between the different bound OH stretches is largest. Here a doublet is observed due to incomplete averaging. DFT calculations indicate that the D-bonded form of HDO(H(2)O)(2) is between 50 and 60 cm(-1) more stable than the H-bonded form. The energy difference is determined by differences in zero point vibration energy of intermolecular librations of the two forms. Attempts to measure the energy difference indicate that the energy difference is larger, of the order of 100 cm(-1).},
  author       = {Ceponkus, J and Uvdal, Per and Nelander, Bengt},
  issn         = {0021-9606},
  language     = {eng},
  number       = {6},
  publisher    = {American Institute of Physics (AIP)},
  series       = {Journal of Chemical Physics},
  title        = {On the structure of the matrix isolated water trimer.},
  url          = {http://dx.doi.org/10.1063/1.3551622},
  doi          = {10.1063/1.3551622},
  volume       = {134},
  year         = {2011},
}