Direct <i>ab initio</i> variational calculation of vibrational energies of the H2O⋯Cl− complex and resolution of experimental differences

Irle, Stephan; Bowman, Joel M.

doi:10.1063/1.1324704

Cited by 64 publications

(43 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 5 presents an overview of the predissociation spectra obtained for all of the hydrates studied here, Cl 2 -‚ (H 2 O) 1-5 , as well as the anharmonicity-corrected frequencies (the B3LYP/aug-cc-pVDZ level) for various structures calculated to be locally stable. Whereas the Cl 2 -‚(H 2 O) 1-2 complexes exhibited only one infrared feature in the 3000-3800-cm -1 region, there are at least six distinct absorption bands for Cl 2 -‚(H 2 O) 3 , and similarly complex spectra are observed for Cl 2 -‚(H 2 O) [4][5] . The presence of this complexity indicates that a variety of hydrogen bonding environments are at play, in contrast to the highly symmetrical ionic H-bonding motif presented in the mono-and dihydrates.…”

Section: Iiia2 Internal Energy Effects: Red Shifting Of the Oh Strmentioning

confidence: 87%

A Cluster Study of Cl₂^- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl₂^-·1−5(H₂O) Series

2004

View full text Add to dashboard Cite

We report argon predissociation spectra of the Cl 2 -‚nH 2 O (n ) 1-5) clusters in the OH stretching region. The spectra of the mono-and dihydrates consist of only a single sharp feature, indicating that the water molecules bind symmetrically to the ion in both cases. The spectra become much more complex in the n ) 3-5 clusters, displaying band positions consistent with the formation of cyclic networks similar to those found in the hydration of other small diatomic anions. We contrast this behavior with that of the related Cl -‚(H 2 O) 1-3 clusters, where the primary difference arises from delocalization of the excess electron density over two atomic centers in the diatomic anion.

show abstract

Section: Iiia2 Internal Energy Effects: Red Shifting Of the Oh Strmentioning

confidence: 87%

A Cluster Study of Cl₂^- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl₂^-·1−5(H₂O) Series

2004

View full text Add to dashboard Cite

show abstract

“…25͒ calculations have been carried out by our group 15 and by Irle and Bowman. 16 Matsunaga, Chaban and Gerber 17 have recently proposed a degenerate perturbation theory for adding correlation corrections to the VSCF results, which is now the default cc-VSCF method in GAMESS. In spite of the large computational cost in direct approaches, successful applications are increasing in number.…”

Section: Introductionmentioning

confidence: 99%

Ab initio vibrational state calculations with a quartic force field: Applications to H2CO, C2H4, CH3OH, CH3CCH, and C6H6

Yagi

Hirao

Taketsugu

et al. 2004

The Journal of Chemical Physics

171

116

View full text Add to dashboard Cite

For polyatomic molecules, n-mode coupling representations of the quartic force field (nMR-QFF) are presented, which include terms up to n normal coordinate couplings in a fourth-order polynomial potential energy function. The computational scheme to evaluate third-and fourth-order derivatives by finite differentiations of the energy is fully described. The code to generate the nMR-QFF has been implemented into GAMESS program package and interfaced with the vibrational self-consistent field (VSCF) and correlation corrected VSCF (cc-VSCF) methods. As a demonstration, fundamental frequencies have been calculated by the cc-VSCF method based on 2MR-QFF for formaldehyde, ethylene, methanol, propyne, and benzene. The applications show that 2MR-QFF is a highly accurate potential energy function, with errors of 1.0-1.9% relative to the experimental value in fundamental frequencies. This approach will help quantitative evaluations of vibrational energies of a general molecule with a reasonable computational cost. Keywords Polynomials, Vibrational states Disciplines Chemistry CommentsThe following article appeared in Journal of Chemical Physics 121 (2004) For polyatomic molecules, n-mode coupling representations of the quartic force field (nMR-QFF) are presented, which include terms up to n normal coordinate couplings in a fourth-order polynomial potential energy function. The computational scheme to evaluate third-and fourth-order derivatives by finite differentiations of the energy is fully described. The code to generate the nMR-QFF has been implemented into GAMESS program package and interfaced with the vibrational self-consistent field ͑VSCF͒ and correlation corrected VSCF ͑cc-VSCF͒ methods. As a demonstration, fundamental frequencies have been calculated by the cc-VSCF method based on 2MR-QFF for formaldehyde, ethylene, methanol, propyne, and benzene. The applications show that 2MR-QFF is a highly accurate potential energy function, with errors of 1.0-1.9% relative to the experimental value in fundamental frequencies. This approach will help quantitative evaluations of vibrational energies of a general molecule with a reasonable computational cost.

show abstract

“…Reasonable IR vibration values for organic molecule can be obtained at the B3LYP/6-31+G(d,p) [23], B3LYP/6-31++G (d,p) [24] and B3LYP/6-311++G(d,p) [25] levels of theory. The advantage of B3LYP/6-311++G(d,p) is that it accurately predicts not only IR properties but also NMR properties, as documented by Vailikhit [26].…”

Section: Gas Phase Calculationsmentioning

confidence: 99%

Characteristic vibration patterns of odor compounds from bread-baking volatiles upon protein binding: density functional and ONIOM study and principal component analysis

et al. 2011

View full text Add to dashboard Cite

As the mechanism underlying the sense of smell is unclear, different models have been used to rationalize structure-odor relationships. To gain insight into odorant molecules from bread baking, binding energies and vibration spectra in the gas phase and in the protein environment [7-transmembrane helices (7TMHs) of rhodopsin] were calculated using density functional theory [B3LYP/6-311++G(d,p)] and ONIOM [B3LYP/6-311++G(d,p):PM3] methods. It was found that acetaldehyde ("acid" category) binds strongly in the large cavity inside the receptor, whereas 2-ethyl-3-methylpyrazine ("roasted") binds weakly. Lys296, Tyr268, Thr118 and Ala117 were identified as key residues in the binding site. More emphasis was placed on how vibrational frequencies are shifted and intensities modified in the receptor protein environment. Principal component analysis (PCA) suggested that the frequency shifts of C-C stretching, CH(3) umbrella, C = O stretching and CH(3) stretching modes have a significant effect on odor quality. In fact, the frequency shifts of the C-C stretching and C = O stretching modes, as well as CH(3) umbrella and CH(3) symmetric stretching modes, exhibit different behaviors in the PCA loadings plot. A large frequency shift in the CH(3) symmetric stretching mode is associated with the sweet-roasted odor category and separates this from the acid odor category. A large frequency shift of the C-C stretching mode describes the roasted and oily-popcorn odor categories, and separates these from the buttery and acid odor categories.

show abstract

Direct ab initio variational calculation of vibrational energies of the H2O⋯Cl− complex and resolution of experimental differences

Cited by 64 publications

References 24 publications

A Cluster Study of Cl₂^- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl₂^-·1−5(H₂O) Series

A Cluster Study of Cl₂^- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl₂^-·1−5(H₂O) Series

Ab initio vibrational state calculations with a quartic force field: Applications to H2CO, C2H4, CH3OH, CH3CCH, and C6H6

Characteristic vibration patterns of odor compounds from bread-baking volatiles upon protein binding: density functional and ONIOM study and principal component analysis

Contact Info

Product

Resources

About

Direct ab initio variational calculation of vibrational energies of the H2O⋯Cl− complex and resolution of experimental differences

Cited by 64 publications

References 24 publications

A Cluster Study of Cl2- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl2-·1−5(H2O) Series

A Cluster Study of Cl2- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl2-·1−5(H2O) Series

Ab initio vibrational state calculations with a quartic force field: Applications to H2CO, C2H4, CH3OH, CH3CCH, and C6H6

Characteristic vibration patterns of odor compounds from bread-baking volatiles upon protein binding: density functional and ONIOM study and principal component analysis

Contact Info

Product

Resources

About

A Cluster Study of Cl₂^- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl₂^-·1−5(H₂O) Series

A Cluster Study of Cl₂^- Microhydration: Size-Dependent Competition between Symmetrical H-Bonding to the Anion and the Formation of Cyclic Water Networks in the Cl₂^-·1−5(H₂O) Series