Kinetics of the gas‐phase reaction between iodine and monogermane and the bond dissociation energy D(H₃GeH)

Abstract

The title reaction has been investigated in the temperature range of 403-446 K. Monoiodogermane and di-iodogermane together with hydrogen iodide were the main products, although a t high conversions a t least one other product was formed. GeHsI is clearly the primary product. Initial rates were found to obey the rate lawover a wide range of initial iodine and monogermane pressures. Secondary reactions (of GeHsI with 12) affect the subsequent kinetics, although a t sufficiently high initial reactant ratios100) an integrated rate equation fits the data with the same rate constants as the initial rate expression. The observed kinetics are consistent with an iodine atom abstraction chain mechanism, and for the step 1

Fourier transform-ion cyclotron resonance study of the gas-phase acidities of germane and methylgermane; Bond dissociation energy of germane

“…At 298.15 K, we obtain 230 ± 9 k] mol-I, which compares with the Noble and Walsh [18] value of 218 ±…”

“…Gas-phase kinetics of hydrogen abstraction has been used to determine the first bond dissociation energy of germane. In such a study, Noble and Walsh [18] reported DO(H 3Ge-H) = 346 ± 10 k] mol"? (believed to be at 298.15 K).…”

“…Thus, each of the three remaining quantities may be derived from the other two. Using the EA(GeH 3 ) value proposed by Reed and Brauman [12] and the DO(H 3Ge-H) value obtained by Noble and Walsh [18], Lias et al [17] estimated the value of the gas-phase acidity of germane. The uncertainty with regard to this value arises mainly from the uncertainty with regard to DO(H 3Ge-H).…”

“…The aH;cidO(H 2S) was corrected to 298.15 K by using tabulated H"-H~functions [30] for H 2S, H+, and HCl (isoelectronic to HS-). From this anchor point, we obtain a gas-phase enthalpy of acidity at 298.15 K for GeH 4 of 1502.0 ± 5.1 k] mol ", The lower accuracy of the tabulated D-EA value [17] is mainly due to the uncertainty of D"(H 3Ge-H) [18]. For MeGeH 3 , the gas-phase enthalpy of acidity was obtained by averaging the data referred to MeCHO and EtCHO.…”

Gas‐Phase Chemistry and Mass Spectrometry ofGe‐,Sn‐ andPb‐Containing Compounds

“…The dynamics of hydrogen abstraction reactions promoted by F, O, OH and OD with monogermane have been studied as a function of the vibrational and rotational state by infrared chemiluminescence 222 -224 . While this technique provides enormous insight on the energy disposal in a reaction, it also led to a value of 326 ± 4 kJ mol −1 for the H 3 Ge−H bond dissociation energy at 0 K. This value is somewhat lower than the value of 346 ± 10 kJ mol −1 obtained from a kinetic study of reaction 44 and its thermochemistry 225,226 .…”