THERMODYNAMIC INVESTIGATION OF SMALL GERMANIUM-TIN CLUSTERS WITH A MASS-SPECTROMETER

The partial pressures of GeSn, Ge2Sn, GeSn2, and Ge3Sn have been measu red above a mixture of tin, silicon, and germanium using the Knudsen e ffusion mass spectrometric method. Partial pressures and estimated the rmal functions yield the atomization enthalpies, Delta H-a,H-o, in kJ mol(-1), of: 230+/-13 (GeSn), 490+/-22 (GeSn2), and 559+/-27 (Ge2Sn). For the molecules Ge3Sn, Ge4Sn, and SnC upper limits (for the atomizat ion enthalpy) have been obtained as: 996+/-32, 1389+/-42, and 452+/-14 , respectively. (C) 1998 American Institute of Physics. [S0021-9606(98 )50932-4].