Department of Physics, A.V.C. College (Autonomous), 14 Sivasakthi Nagar, Mappadugai, Mayiladuthurai, Nagai District 609305, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2010 Jun;76(1):84-92. doi: 10.1016/j.saa.2010.02.050. Epub 2010 Mar 6.
The FTIR and FTRaman spectra of 2-bromo-4-methyl aniline (2-B-4-MA) molecule have been recorded using Brucker IFS 66V spectrometer in the range of 4000-100 cm(-1). The molecular geometry and vibrational frequencies in the ground state are calculated using the Hartree-Fock (HF) and B3LYP with 6-31+G*(d, p), 6-311+G*(d, p) and 6-311++G* (d, p) basis sets. The computed values of frequencies are scaled using a suitable scale factor to yield good coherence with the observed values. The isotropic HF and DFT analysis showed good agreement with experimental observations. Comparison of the fundamental vibrational frequencies with calculated results by HF and B3LYP methods indicates that B3LYP/6-311++G* (d, p) is superior to HF/6-31+G* for molecular vibrational problems. The complete data of this title compound provide the information for future development of substituted aniline. The influences of bromine atom, methyl group and amine group on the geometry of benzene and its normal modes of vibrations have also been discussed.
采用 Brucker IFS 66V 光谱仪在 4000-100cm(-1) 范围内记录了 2-溴-4-甲基苯胺（2-B-4-MA）分子的 FTIR 和 FTRaman 光谱。使用 Hartree-Fock（HF）和 B3LYP 方法，在 6-31+G*（d，p）、6-311+G*（d，p）和 6-311++G*（d，p）基组上计算了分子的几何形状和基态振动频率。通过适当的标度因子对计算得到的频率进行了标度，以与观察到的值具有良好的一致性。各向同性 HF 和 DFT 分析与实验观测结果吻合较好。与 HF 和 B3LYP 方法的计算结果相比，基本振动频率的比较表明，对于分子振动问题，B3LYP/6-311++G*（d，p）优于 HF/6-31+G*。该标题化合物的完整数据为取代苯胺的进一步发展提供了信息。还讨论了溴原子、甲基和胺基对苯的几何形状及其振动模式的影响。
