The present invention relates to the process of selectively exposing matter to a specific wavelength of electromagnetic energy in sufficient flux density per wavelength to cause or promote a desired effect. The process includes, but is not limited to, destroying, disinfecting, denaturing, disinfesting, disrupting, or dehydration of one or more of the substances present. More specifically, present invention relates to subjecting matter, which may contain a mixture of substances, to electromagnetic energy, in concurrence with its spectral properties to exploit the spectral differences within the substance or within a mixture of substances. Energies are applied to cause wavelength-dependent reactions resulting from differential absorption; this additional applied energy manifests itself in changes, or quantum transitions, in the vibrational, rotational, magnetic, and electronic states of the molecules. Generally, the process utilizes wavelengths from about one light second to about ten electron volts, or wavelengths with energy levels less than that of ionization.