4-Methyl-1H-Indazole-5-Boronic acid: Crystal structure, vibrational spectra and DFT simulations

Molecular structure, conformer forms, geometric parameters and vibrational assignments and properties of 4-Methyl-1H-Indazole-5-Boronic Acid (4M1HI5BA) were theoretically and experimentally studied using Raman, FT-IR, XRD spectroscopic methods and quantum chemical calculations. Raman and FT-IR spectra were examined range from 4000 to 400 cm−1. Moreover, single crystals of 4M1HI5BA were prepared in order to use in XRD experiments. Vibrational assignments were carried out using total energy distribution (TED) values. Furthermore, HOMO and LUMO were calculated for 4M1HI5BA. Four different conformations of 4M1HI5BA were calculated in only gas phase. The theoretical and experimental results show that in order to predict vibrational wavenumbers B3LYP/6-311++G(d,p) may provide acceptable results and the most stable conformer of 4M1HI5BA is predicted to be envelope conformer.