Rai Vineet Kumar, Rai Amareswar, Rai D K, Rai S B
Department of Physics, Laser and Spectroscopy Laboratory, Banaras Hindu University, Varanasi 221 005, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2004 Jan;60(1-2):53-6. doi: 10.1016/s1386-1425(03)00179-3.
Overtone spectra of 2-ethylaniline, N-methylaniline, N-ethylaniline, N,N-dimethylaniline and N,N-diethylaniline have been studied in 2500-15000 cm(-1) region. Vibrational frequency and anharmonicity constants for aryl/alkyl C-H stretch and N-H stretch vibrations have been determined. The effect of substitution of C(2)H(5) group on the ortho position in the ring and CH(3)/C(2)H(5) at the positions of the H-atom in NH(2) group has been studied in these molecules. It is noted that the aryl C-H stretching frequency and the N-H stretching frequency is appreciably increased due to the replacement of H in NH(2) group by CH(3)/C(2)H(5). These experimental observations are well supported by theoretical calculations for charge density on N-atom using molecular orbital AM(1) method.
