FOURIER TRANSFORM-ION CYCLOTRON-RESONANCE STUDY OF THE GAS-PHASE ACIDITIES OF GERMANE AND METHYLGERMANE - BOND-DISSOCIATION ENERGY OF GERMANE

An accurate gas-phase acidity for germane (enthalpy scale, equivalent to the proton affinity of GeH3-), DELTAH(acid)degrees(GeH4) = 1502.0 +/- 5.1 kJ mol-1, is obtained by constructing a consistent acidity ladder between GeH4 and H2S by using Fourier transform-ion cyclotron resonance spectrometry, and 0 and 298.15 K values for the first bond dissociation energy of GeH4 are proposed: D0-degrees(H3Ge-H) = 352 +/- 9 kj mol-1; D-degrees(H3Ge-H) = 358 +/- 9 kj mol-1, respectively. These results are compared with experimental and theoretical data reported in the literature. Methylgermane was found to be a weaker acid than germane by approximately 35 kj mol-1: DELTAH(acid)degrees(MeGeH3) = 1536.6 kj mol-1.