Title
Prediction of spectroscopic constants for diatomic molecules in the ground and excited states using time-dependent density functional theory
Abstract
Spectroscopic constants of the ground and next seven low-lying excited states of diatomic molecules CO, N-2, P-2, and ScF were computed using the density functional theory SAOP/ATZP model, in conjunction with time-dependent density functional theory (TD-DFT) and a recently developed Slater type basis set, ATZP. Spectroscopic constants, including the equilibrium distances r(e), harmonic vibrational frequency omega(e), vibrational anharmonicity omega(e)x(e), rotational constant B-e, centrifugal distortion constant D-e, the vibration-rotation interaction constant alpha(e), and the vibrational zero-point energy E-n(0), were generated in an effort to establish a reliable database for electron spectroscopy. By comparison with experimental values and a similar model with an established larger Slater-type basis set, et-QZ3P-xD, it was found that this model provides reliably accurate results at reduced computational costs, for both the ground and excited states of the molecules. The over all errors of all eight lowest lying electronic states of the molecules under study using the effective basis set are r(e)(+/- 4%), omega(e)(+/- 5% mostly without exceeding +/- 20%), omega(e)x(e)(+/- 5% mostly without exceeding 20%, much more accurate than a previous study on this constant of +/- 30%), B-e(+/- 8%), D-e(+/- 10%), alpha(e)(+/- 10%), and E-n(0)(+/- 10%). The accuracy obtained using the ATZP basis set is very competitive to the larger et-QZ3P-xD basis set in particular in the ground electronic states. The overall errors in r(e), omega(e)x(e) and alpha(e) in the ground states were given by +/- 0.7, +/- 10.1, and +/- 8.4%, respectively, using the efficient ATZP basis set, which is competitive to the errors of +/- 0.5, +/- 9.2, and +/- 9.1%, respectively for those constants using the larger et-QZ3P-xD basis set. The latter basis set, however, needs approximately four times of the CPU time on the National Supercomputing Facilities (Australia). Due to the efficiency of the model (TD-DFT, SAOP and ATZP), it will be readily applied to study larger molecular systems. (c) 2005 Wiley Periodicals, Inc.
Year
DOI
Venue
2006
10.1002/jcc.20330
JOURNAL OF COMPUTATIONAL CHEMISTRY
Keywords
Field
DocType
spectroscopic constants,diatomic molecules,ground state,excited states,Density Function Theroy
Excited state,Rotational spectroscopy,Ground state,Diatomic molecule,Atomic physics,Anharmonicity,Computational chemistry,Chemistry,Density functional theory,Basis set,Time-dependent density functional theory
Journal
Volume
Issue
ISSN
27
2
0192-8651
Citations 
PageRank 
References 
0
0.34
4
Authors
3
Name
Order
Citations
PageRank
Chantal T. Falzon111.12
Delano P. Chong251.87
Feng Wang3387.16