Matrix isolation is an experimental technique used in
chemistry and
physics which generally involves a material being trapped within an unreactive
matrix. A
host matrix is a continuous
solid phase in which
guest particles (atoms, molecules, ions, etc.) are embedded. The guest is said to be
isolated within the host matrix. Initially the term matrix-isolation was used to describe the placing of a
chemical species in any unreactive material, often
polymers or
resins, but more recently has referred specifically to
gases in low-temperature solids. A typical matrix isolation experiment involves a guest sample being diluted in the gas phase with the host material, usually a
noble gas or
nitrogen. This mixture is then deposited on a window that is cooled to below the melting point of the host gas. The sample may then be studied using various
spectroscopic procedures.