Rate constants for the gas-phase reactions of germylene with CH3OCH3, CH3OH, CD3OD and D2O at ambient temperature

Abstract

Gas-phase rate constants for the reactions of germylene, GeH 2 , with dimethylether (CH 3 OCH 3 ), methanol (CH 3 OH), deuterated methanol (CD 3 OD), and deuterated water (D 2 O), have been determined at ambient temperature (295 K) and total pressures over the range 10-200 Torr of the bath gas SF 6 . The second-order rate constants are pressure dependent up to the maximum pressures investigated. The behaviour of GeH 2 with these reactants is very similar to the behaviour observed for silylene, SiH 2 . Over the same pressure range the GeH 2 reaction rate constants are smaller than those observed for SiH 2 .

Gas phase kinetic and theoretical studies of reactions of germylenes and dimethylstannylene

“…100 Deuterated shows that GeH 2 is less reactive toward these O donor molecules. 100 As has been discussed above, this decrease in reactivity on going from SiH 2 to GeH 2 was also observed in the addition and inser tion reactions.…”

“…Above ca. 100 Torr, the signals of the transient species became too weak to be measured reliably, and below 1 Torr, pressure measurement uncertainties be came significant. In the studies of the temperature depen dence of the rate constants, the series of experiments described above was repeated at different temperatures (usually, five) between room temperature and the highest temperature allowed by the stabilities of either the precur sor or the substrate.…”

“…In fact, the values obtained for the rate constants measured for the reaction GeH 2 + D 2 O at 30 and 100 Torr (with SF 6 as the bath gas) were nominally the same. 100 Because the reaction GeH 2 + D 2 O was expected to be faster than the reaction GeH 2 + H 2 O, the kinetics of the latter were not studied. 100 The reactions of GeH 2 with Me 2 O, MeOH, and CD 3 OD are much faster and show clear pressure depen dences (see Table 10).…”

“…100 Because the reaction GeH 2 + D 2 O was expected to be faster than the reaction GeH 2 + H 2 O, the kinetics of the latter were not studied. 100 The reactions of GeH 2 with Me 2 O, MeOH, and CD 3 OD are much faster and show clear pressure depen dences (see Table 10). All of them remain in the fall off region up to pressures of 200 Torr at least.…”

“…100 As a result, the rate constants were determined with large uncertainties (Table 10). A similar reaction of SiH 2 with H 2 O is also slow.…”