DISSOCIATION-ENERGIES OF THE GA-2, IN-2, AND GAIN MOLECULES

The group III metal dimers Ga-2 and In-2 and the newly identified inte rmetallic molecule Gain were investigated in a Knudsen cell-mass spect rometric study of the vapors over gallium-indium alloys. From the all- gas equilibria analyzed by the second-law and third-law methods the fo llowing dissociation energies were derived; D-0(0) (Ga-2)=110.8+/-4.9 kJ mol(-1), D-0(0) (In-2)=74.4+/-5.7 kJ mol(-1) D-0(0) (GaIn)=90.7+/-3 .7 kJ mol(-1). The value here measured for the dissociation energy of In-2 is discussed and compared with a previous experimental determinat ion and with the results of more recent theoretical investigations. (C ) 1998 American Institute of Physics.