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Comparison of the Room Temperature Rate Constants for the Reaction OH + ROH Determined by Different Techniques ku X 10"12 (cm3 mol"1 s"') Reactant This work Lit. value Ref CH3OH 0.64 ± 0.06 0.57 ± 0.06 4°0 .12 ± 0.02 3b 0.90 16c c2h5oh 2.25 ± 0.22 1.8 ± 0.2 4°1 .85 16c i-c3h,oh 3.21 ± 0.32 2.3 ± 0.2 4°2 .8 16c 2-C3H,OH 3.30 ± 0.33 4.3 ± 1.3 5d 2.15 16e 0Relative to the rate constant OH + n-butane, for which a value of 1.4 X 1012 cm3 mol"1 s"1 has been used. b Relative to the rate constant of OH with CO, for which we used the high pressure value of 1.9 X 10" cm3 mol"1 s'1.6 c Liquid phase determination; OH was generated by pulse radiolysis of H,0. Rate constants are mean values reported in ref 16. d The ráte constant was determined at 305 K, relative to the rate constant of OH + isobutene at 305 K, for which a value of 3.05 X 1013 cm3 mol"1 s"1 has been used. error from the secondary reaction 2.As mentioned in the Introduction all the other studies are relative determinations. Our values agree well with those of Campbell et al.4 for CH3OH and C2H5OH, while for l-C3H7OH their value is ~30% lower than ours; they used a rate constant for the reaction of OH + n-butane of 1.4 X 1012 cm3 mol"1 s"1, if the more recent value of 1.65 X 1012 cm3 mol"1 s"1 is used,15 very good agreement is obtained for all alcohols. Our value for 2-C3H7OH is somewhat lower than, but within the wide error limits of

Near-surface (∼1000 Å) modification in the net carrier concentration in n-type InP (n=6×1015–1.5×1017 cm−3) was observed after reactive ion etching (RIE) in Cl-based (CCl2F2/O2) or organic-based (C2H6/H2) discharges. The carrier loss is slightly more pronounced in the latter case, due possibly to the creation of deep level, compensating acceptors at greater depths as a result of implantation of the light hydrogen ions. Near-complete recovery of the initial carrier density occurs after annealing at 500 °C for 30 s. Structural disorder is detected by ion channeling to depths of ∼400 Å after C2H6/H2 RIE with a self-bias of 380 V. This disorder shows significant recovery after 400 °C, 30 s annealing. Current-voltage measurements on Au Schottky diodes showed ohmic behavior after etching of the InP in a C2H6/H2 discharge, due to the nonstoichiometric surface remaining after RIE. Diodes fabricated on CCl2F2/O2 etched material show only a slight increase in reverse current compared to unetched control samples.

The results of microwave and radio frequency spectroscopy of the weakly bound complexes of hydrogen fluoride with carbon dioxide and carbonyl sulfide are presented. The following spectroscopic constants are determined:                           A nearly linear hydrogen bonded equilibrium structure with an O–H bond length of ∼1.9 Å is consistent with all the experimental data. The stretching force constant, estimated from the distortion constant to be ks = 0.021 mdyne/Å for CO2–HF, appears anomalously small for such a short bond.