Microwave spectra and ab initio calculations of 1-nitropyrazole
The microwave (MW) spectrum of 1-nitropyrazole obtained at room temperature is presented, together with ab initio MP2/6-31G∗∗ calculations on its structure and harmonic vibrational frequencies. The initial assignment of the spectrum was carried out using a radio frequency—microwave double resonance (RFMWDR) technique. Both experimental and theoretical results indicate that 1-nitropyrazole is a planar molecule. The structure obtained from the MW spectrum agrees fairly well with that obtained at the MP2(FULL)/6-31G∗∗ level.