The spectral dependence of the photoionization efficiency of HSSH was obtained over the wavelength range 110-140 nm by means of a discharge flow and a photoionization mass spectrometer coupled to a synchrotron as the radiation source. The HSSH was generated in the flow tube at room temperature via the sequential reactions: O + H 2 S f OH + HS; HS + HS (+ M) f HSSH (+ M), M being any third body. The ionization energy of HSSH was determined to be 9.40 ( 0.02 eV. This result agrees satisfactorily with the reported value measured from photoelectron spectra. The heat of formation of the ion HSSH + , ∆ f H°2 98 (HSSH + ), was calculated to be 220.6 ( 2 kcal mol -1 . The generation of HSSH from the self-reaction of HS radicals might indicate a previously neglected role in the atmospheric sulfur cycle.

The spectrum of photoionization efficiency (PIE) of S2O2 was measured in the spectral range 105–130 nm by means of a discharge flow and a photoionization mass spectrometer coupled to a synchrotron as a radiation source. S2O2 was generated from self reaction of SO radicals, SO+SO→S2O2, in a gaseous flow system. SO radicals were produced on reacting O atoms with CS2 and OCS. The ionization energy (IE) of S2O2 was determined to be (9.93±0.02) eV.

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Ethylthio (C2H5S) radicals were formed on laser photolysis at 248 nm of diethyl disulfide (C2H5SSC2H5) or ethyl mercaptan (C2H5SH) in a free-jet expansion. The fluorescence excitation spectrum was recorded in the spectral region 398–432 nm. The origin lies at 23 519.6 cm−1, approximately 799 cm−1 greater than previously reported. Two main progressions with spacings near 420.5 cm−1 (C–S stretch) and 256.0 cm−1 (CCS bend) are dominant. Additional active fundamental vibrational modes of the B̃ state are at 718.4, 862.8, 1054.6, 1158.9, and 1203.3 cm−1. Observation of hot bands enables accurate determination of four low-lying vibrational modes of the ground state at 271.9, 296.0, 478.3, and 672.4 cm−1. The dispersed fluorescence was recorded in the spectral region 415–525 nm. We identified several additional vibrational modes of the X̃ state at 890, 957, 1075, 1257, 1290, 1470, 2950, and 3050 cm−1. Theoretical calculations at the MP2 level were performed to predict vibrational frequencies of both B̃ and X̃ states, and for the latter state were also with the B3-LYP density functional theory; the results agree satisfactorily with experimental observations.

Nickel nanoparticles were synthesized by the chemical reduction of NiCl2 with N2H4 under controlled pH environment. During nucleation, polyvinyl pyrrolidone (PVP) was added as the protective agents for preventing the agglomeration of metal clusters. Color of the solution changed from green to blue during the reaction period. X-Ray Adsorption Spectroscopy (XAS), X-Ray Diffraction (XRD), and Transmission Electron Microscopy (TEM) analytical methods were used to characterize the product. XAS analysis showed that the reduction reaction occurred within 5 minutes after the addition of N2H4. The length of Ni-Ni bond was 2.59 nm. The results of XRD analysis of the three cases with pH ranging from 11.0 to 13.0 suggest that the optimum pH value for the reaction appeared to be 12.0. The average particle size was 20-50 nm under this condition.