US EPA

6919317 

Journal Article 

Comparative vibrational analysis of 1,2-Dinitro benzene and 1-Fluoro-3-nitro benzene: A combined experimental (FT-IR and FT-Raman) and theoretical study (DFT/B3LYP/B3PW91) 

Mahadevan, D; Periandy, S; Ramalingam, S; , 

2011 

1 

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
ISSN: 1386-1425
EISSN: 1873-3557 

PERGAMON-ELSEVIER SCIENCE LTD 

OXFORD 

84 

1 

86-98 

English 

21993260 

10.1016/j.saa.2011.09.004 

WOS:000297450400012 

In this work, the comparative analysis is made on the structure and vibrational spectra of 1,2-Dinitro benzene (1,2-DNB) and 1-Fluoro-3-nitro benzene (1-F-3-NB) molecules. The FT-IR and FT-Raman experimental spectra of the molecules have been recorded using Bruker IFS 66V spectrometer in the range of 4000-100 cm(-1). Making use of the recorded data, the complete vibrational assignments are made and analyses of the observed fundamental bands of molecules are carried out. The experimental determinations of vibrational frequencies are compared with those obtained theoretically from ab-initio Hartree-fock (HF) and DFT (B3 LYP and B3 PW91) methods with 6-31++G (d, p) and 6-311++G (d, p) basis sets. The differences between the observed and scaled wave number values of most of the fundamentals of the molecules are very small in B3 LYP than HF. The geometries and normal modes of vibrations obtained from ab-initio HF and B3LYP/B3PW91 calculations are compared with the experimentally observed data. Comparison of the simulated spectra of the molecules provides important information regarding the difference and similarity of the vibrational characteristics between the molecules. The impact of substitutions on the structures between the molecules is also investigated. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved. 

1,2-Dinitro benzene; 1-Fluoro-3-nitro benzene; Ab-initio Hartree-fock; Bruker IFS; FT-Raman