Spectroscopic characteristics and X-ray induced transformations of the HCN⋯CO complex in solid Ar and Kr matrices were studied by FTIR spectroscopy and ab initio calculations at the CCSD(T) level. The complex was prepared by deposition of the HCN/CO/Ng gas mixtures (Ng = Ar or Kr). The comparison of the experiment and calculations prove formation of a linear, H-bonded NCH⋯OCO complex with a substantial red shift of the C-H stretching band and a blue shift of the H-C-N bending band in respect to the monomer. This result is in contrast with the previous gas-phase observations, where only T-shape complex was found. Irradiation of deposited matrices leads to formation of CN radicals and HNC molecules and subsequent annealing results in appearance of HCN and trans-HCNH in both matrices plus HKrCN in the case of Kr. In the presence of CO, the strongest absorption of trans-HCNH radical demonstrates an additional blue-shifted (by 6.4 cm) feature, which was assigned to the N-coordinated complex of this radical with CO on the basis of comparison with calculations. To our knowledge, it is the first experimentally observed complex of this radical. No evidence was found for HKrCN⋯CO complex, which was explained tentatively by steric hindrance.

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The hyperfine coupling constant of the hydrogen atom has been measured in pressurized liquid water up to 300 °C. The reduced constant A(water)∕A(vacuum) is 0.9939 at room temperature, and decreases to a minimum of 0.9918 at 240 °C. The reduced constant then increases at higher temperature. The g-factor is 2.002244(10) at room temperature and decreases to 2.00221(1) at 240 °C. The change in g-factor is proportional to the change in hyperfine coupling. The behavior below 110 °C is in excellent agreement with a previously proposed model in which the H atom is confined to a harmonic solvent cage, and vibrations within the cage mix "p-type" character into the wavefunction, resulting inA(water)∕A(vacuum) < 1. The harmonic model breaks down above 130 °C. We demonstrate that a classical binary collision model using approximate partial molar volume information can recover the observed minima near 240 °C.

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The mechanism for acid production in phenolic extreme ultraviolet (EUV) lithography films containing triphenylsulfonium triflate (Ph(3)S(+)TfO(-)) acid generator has been investigated by electron paramagnetic resonance (EPR) spectroscopy and by use of the acid indicator coumarin 6 (C6). Gamma radiolysis was substituted for the EUV radiation with the assumption that the chemistry generated by ionization of the matrix does not depend on the ionization source. Poly(4-hydroxystyrene) (PHS) was first investigated as a well-studied standard, after which the water-wheel-like cyclic oligomer derivative containing pendant adamantyl ester groups, noria-AD(50), was investigated. EPR measurements confirm that the dominant free radical product is a phenoxyl derivative (PHS-O(•) or noria-O(•)) that exhibits quite slow stretched exponential recombination kinetics at room temperature. Also observed at 77 K was the presence of a significant hydrogen atom product of radiolysis. The G value or yield of acid production in thin lithography films was measured with the C6 indicator on a fused silica substrate. It was found that a significant amount of acid is generated via energy transfer from the irradiated fused-silica substrate to the Ph(3)S(+)TfO(-) in the films. By varying the film thickness on the substrates, the substrate effect on the acid yield was quantitatively determined. After subtraction of the contribution from the substrates, the acid yield G value in the PHS film with 10 wt % Ph(3)S(+)TfO(-) and 5 wt % C6 was determined to be 2.5 ± 0.3 protons per 100 eV of radiation. The acid yield of noria-AD(50) films was found to be 3.2 ± 0.3 protons per 100 eV.