ON STRUCTURES,PROPERTIES AND CHEMICAL BOND OF Te-Se-I GLASS AND OF ADDING As,Ge ELEMENTS ONE

摘要

Te-Se glass and adding As,Ge elements to itare studied with Selt-Consistent-Field Discrete Variatioal X_α(SEF-DV-X_α),one of the molecule orbital calculating meth-ods in quantum chemistry.The chemical bonding is used todiscuss the relations between structures and properties with thevarations of compositions of the glasses.The calculated re-sults show that the strength of covalent and ionic bonds areboth in the order of Ge-SeAsSeTe-Se,which is consis-tent with the experimental result of the glass-transition tem-perature(T_g) of the corresponding glasses.The Te-I bond inwhich Ⅰ atom is one-coordinate is sstronger than that in whichⅠ atom is two-coordinate,As-Ⅰ and As-As bonds are bothstronger than the two types of Te-Ⅰ bonds.The waek Te-Ⅰbonds have been replaced by the stronger As-Ⅰ and As-Asbonds,which is just the reason why As addition in TeX glass-es can obviously improve the thermal and chemical properties.