What is band spectra?

Band spectra are the emission spectra of molecules, consisting of a series of discrete lines that are closely spaced together and overlapping, forming a band-like appearance. These spectra arise from the rotational and vibrational transitions of the molecule, which occur due to excitation of the electrons of the molecule. The band spectra are unique for each substance and are used in the identification and analysis of molecular compounds. The spacing of the lines in the band spectra is dependent on the energy levels of the molecule and the interactions between its constituent atoms. The study of band spectra has contributed significantly to the development of modern spectroscopic techniques and has applications in many fields, including atmospheric science, astrophysics, and material analysis.