Experimental and computational study on molecular structure and vibrational analysis of a modified biomolecule: 5-Bromo-2′-deoxyuridine

In the present study, the experimental and theoretical vibrational spectra of 5-bromo-2′-deoxyuridine were investigated. The experimental FT-IR (400–4000 cm−1) and μ-Raman spectra (100–4000 cm−1) of the molecule in the solid phase were recorded. Theoretical vibrational frequencies and geometric parameters (bond lengths and bond angles) were calculated using ab initio Hartree Fock (HF) and density functional B3LYP method with 6-31G(d), 6-31G(d,p), 6-311++G(d) and 6-311++G(d,p) basis sets by Gaussian program, for the first time. The assignments of vibrational frequencies were performed by potential energy distribution by using VEDA 4 program. The optimized geometric parameters and theoretical vibrational frequencies are compared with the corresponding experimental data and they were seen to be in a good agreement with the each other. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies were found.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The FT-IR and μ-Raman spectra of BrDU are recorded in solid phase. ► Theoretical vibrational modes and molecular structure are given for the first time. ► The assignments of vibrational frequencies were performed using VEDA 4 program. ► BrDU is mainly used as anti-tumor agent in cancer treatments.