<span style="font-size:10.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-US">FT-IR, FT-Raman and theoretical NBO, NLO and MESP analysis of 4-bromoveratrole by <i style="mso-bidi-font-style:normal">ab-initio</i> HF and DFT methods</span>

Abstract

The Fourier Transform Infrared (FTIR) and FT-Raman spectra of 4-bromoveratrole (4BV) have been recorded in the region 4000-400 cm^{<span style="font-family:Symbol;mso-ascii-font-family: " times="" new="" roman";mso-hansi-font-family:"times="" roman";mso-char-type:symbol;="" mso-symbol-font-family:symbol"="" lang="EN-GB">-1</span>} and 3500-50 cm^{<span style="font-family:Symbol;mso-ascii-font-family: " times="" new="" roman";mso-hansi-font-family:"times="" roman";mso-char-type:symbol;="" mso-symbol-font-family:symbol"="" lang="EN-GB">-1</span>}, respectively. The experimental vibrational frequencies are compared with the wave numbers obtained theoretically by <i style="mso-bidi-font-style:normal">ab-initio </i>HF and DFT-B3LYP gradient calculations employing the standard 6-311++G(d,p) basis set for the optimized geometry of 4BV. The values of the first-order hyperpolarizability (β) of the investigated molecule are computed using DFT quantum mechanical calculations. The calculation results also show that the molecule might have microscopic nonlinear optical (NLO) behaviour with non-zero values.NBO analysis has been carried out at DFT level. NBO study explains charge delocalization of the molecule. Mulliken’s net charges have been calculated and compared with the atomic natural charges.