AB INITIO HF AND DFT STUDIES ON MOLECULAR STRUCTURE AND VIBRATIONAL ANALYSIS OF 2,5-DIBROMOPYRIDINE

Abstract

Theoretical study on molecular structure and vibrational spectra of 2,5-dibromopyridine (2,5-DBP) have been investigated. The optimized geometry, theoretical vibration frequencies and intensities were calculated by using ab initio Hartree-Fock and density functional B3LYP method with 6-31G(d,p) basis sets. The vibrational analysis of title molecule was done and its optimized geometry parameters (bond lengths and bond angles) were given. Scaled theoretical frequencies have been compared with experimental spectra. Observed and calculated frequencies have been shown good agreement. Furthermore, from the comparison it was concluded that the B3LYP method is superior to the HF method for molecular structure and vibrational frequencies.

Keywords

• 2,5-dibromopiridin, Hartree-Fock, DFT, IR spektrumu

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