ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The adiabatic I.P. of Si2H6 obtained by a photoionization mass spectrometric study at two temperatures is 9.74±0.02 eV. The first fragment, Si2H+4, initially appears with a shallow slope at ≤10.04±0.02 eV, and with a much steeper slope at ≤10.81±0.02 eV. It is argued that the initial onset corresponds to formation of H2SiSiH+2, while the steeper onset is attributed to formation of H3SiSiH+. The second fragment, Si2H5, has an appearance potential of ≤11.59±0.02 eV (11.41±0.03 is a probable value). Successive decomposition leads to Si2H+2 (from Si2H+4 ) and Si2H+3 (from Si2H+5 ). The photoion yield curve for Si2H+3 also displays shallow and steep onsets. Upper limits for the appearance potentials can be readily extracted, but the true thermochemical onsets are less well defined. Heats of formation (or upper limits) are presented for each of these species. For Si2H+6, Si2H+5, and Si2H+4, the experimental values are in good agreement with recent ab initio calculations. For the daughter species, the experimental values exceed the calculated ones, as expected.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.460946
