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Updated: Apr 30, 2026

Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Conformational stability, spectroscopic (FT-IR & FT-Raman), HOMO-LUMO, NBO and thermodynamic function of
V Balachandran1, M Murugan2, V Karpagam3
1Research Department of Physics, AA Government Arts College, Musiri, Tiruchirappalli 621211, India.
Abstract:
FT-IR and FT-Raman spectra of 4-(trifloromethoxy) phenol (4TFMP) have been recorded in the regions 4000-400 cm(-1) and 3500-100 cm(-1), respectively. The total energy calculations of 4TFMP were tried for the possible conformers. The molecular structure, geometry optimization, vibrational frequencies were obtained by the DFT level of theory (B3LYP) with the standard basis sets 6-31+G(d) and 6-311++G(d,p). The harmonic frequencies were calculated and the scaled values were compared with experimental FT-IR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The chemical parameters were calculated from the HOMO and LUMO values. Molecular electrostatic potential (MEP) were calculated and analyzed. The thermodynamic functions (heat capacity, entropy, enthalpy) from spectroscopic data by statistical methods were obtained for the range of temperature 100-1000 K.
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