A new method is proposed for controlling the composition (nonstoichiometry) of low-volatile inorganic compounds. The basic principle of the method is the introduction (or removal) of one of the components into the low-volatile compound using reversible selective chemical vapor transport (CVT). Theoretical analysis is used to identify the process parameters determining the direction of mass transport: source temperature T 1 , source composition x 1 , and sample temperature T 2 . Using nonequilibrium thermodynamics concepts, steadystate conditions are found under which mass transport ceases. A new type of phase diagram, x 2 -T 1 -T 2 , is proposed, which describes the state of CVT systems under steady-state conditions without mass transport. The CVT process is used to prepare GaSe crystals with different deviations from stoichiometry. The crystals are characterized using x-ray diffraction and cathodoluminescence spectroscopy. The stability regions of two GaSe polytypes in the T -x phase diagram are located. CVT is used to control the compositions of phases in the In-S system. The advantages of the CVT method are analyzed with application to control over the composition of inorganic compounds. S102 INORGANIC MATERIALS Vol. 40 Suppl. 2 2004 ZAVRAZHNOV et al .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.