Advanced search
Start date
Betweenand
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Fully Anharmonic Vibrational Resonance Raman Spectrum of Diatomic Systems

Full text
Author(s):
Costa, Gustavo J. [1] ; Borin, Antonio C. [2] ; Custodio, Rogerio [3] ; Vidal, Luciano N. [1]
Total Authors: 4
Affiliation:
[1] Univ Tecnol Fed Parana, Dept Acad Quim & Biol, Av Dept Heitor de Alencar Furtado 5000, BR-81280340 Curitiba, PR - Brazil
[2] Univ Sao Paulo, NAP Photo Tech USP Consortium Photochem Technol, Inst Chem, Dept Fundamental Chem, Av Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil
[3] Univ Estadual Campinas, Inst Quim, R Josue de Castro 126, BR-13083970 Campinas, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Source: JOURNAL OF CHEMICAL THEORY AND COMPUTATION; v. 14, n. 2, p. 843-855, FEB 2018.
Web of Science Citations: 0
Abstract

A study is presented on the resonance Raman (RR) spectrum based on fully anharmonic wave functions and energies obtained from ab initio multireference potential energy curves of diatomic systems. The vibrational problem is numerically solved using a variational stochastic method or the Cooley-Numerov method, as implemented in Le Roy's LEVEL program. Anharmonic Franck-Condon and Herzberg-Teller integrals are numerically evaluated, and the RR polarizability is calculated within the time-independent framework of the RR theory. At the harmonic level, the differential cross sections show faster convergence with respect to the number of intermediate vibrational states than what is obtained from anharmonic wave functions. Twice as many intermediate states are required to achieve the same convergence in the RR intensities as observed within the harmonic model. The anharmonic spectra evaluated for H-2, C-2, and O-2 molecules show that RR intensities are strongly affected by anharmonic effects. They differ from their harmonic counterparts not only in the position of the peaks but also in the absolute and relative intensities. (AU)

FAPESP's process: 13/08293-7 - CCES - Center for Computational Engineering and Sciences
Grantee:Munir Salomao Skaf
Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC
FAPESP's process: 17/11485-6 - Computational and theoretical developments based on ab initio methods and the Density Functional Theory
Grantee:Rogério Custodio
Support type: Regular Research Grants