Stabilization of high-temperature noble gas matrices

Previously matrix isolation studies of vibrational energy relaxation and matrix dynamics using high-resolution infrared absorption have been limited to those molecules that were sufficiently soluble in noble gas liquids at cryogenic temperatures. A simple method is described here that can extend the useful temperature range while employing conventional matrix preparation techniques. A less volatile nonabsorbing overcoat is condensed onto the matrix which has been prepared using conventional pulse or continuous deposition methods. Use of the method has been limited to using pure Xe as an overcoat on Ar or Kr matrices and has performed satisfactorily for temperatures up to 600K. The nu3 region for SF6 in an Ar/SF6+10,000 matrix both before and after annealing is shown as an example of use of the method. Studies carried out on CH3F, CD3F, and Ni(CO)4 in Ar matrix are discussed briefly