UV-visible spectroscopy investigates the interactions between ultraviolet or visible electromagnetic radiation and matter. UV-visible spectroscopic measurements provide precise information about atomic and molecular structure. The foundation of UV-visible spectroscopy was laid by English physicist and mathematician Sir Isaac Newton who, by diffracting white light through a prism, showed that it consisted of light of several colors ranging from violet to red. This is now termed the UV-visible electromagnetic spectrum. The red end of the spectrum corresponds to electromagnetic radiation of longer wavelengths (780 nm) and lower frequencies, while the violet end is associated with shorter wavelengths (380 nm) and higher frequencies. An understanding of the dual nature of light, however, which consists of particles called photons that also behave like waves, and of its interaction with matter, waited for the advent of quantum theory. German physicist Maxwell Planck (1858-1947) first postulated that the energy of the electromagnetic spectrum...