J. Stephen Binkley

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This does not exclude the possibility, that larger structural fragments (such as tetramers and pentamers) can also contribute to the low-frequency vibrational spectrum around the boson peak. On the basis of these results, the following model of the glass transition of glycerol can be proposed. At temperatures far above Tg (186 K), the lifetime of the MRO or(More)
as analog computer. The different sizes of C and Si are simulated with tetrahedral joints whose arm lengths differ[*] and the atoms are joined by flexible bonds (bent bonds). In disilabicyclo[l .1 .O]butane C,Si,H, (2) the region between the two C atoms does have a high ELF value (Fig. 1 c and 1 d). This confirms the previously described bond.['] The(More)
A set of data preprocessing algorithms for peak detection and peak list alignment are reported for analysis of liquid chromatography-mass spectrometry (LC-MS)-based metabolomics data. For spectrum deconvolution, peak picking is achieved at the selected ion chromatogram (XIC) level. To estimate and remove the noise in XICs, each XIC is first segmented into(More)
Ab initio molecular orbital theory is used to examine the singlet and triplet potential energy surfaces for the CH2N+ system. The results confirm those of earlier studies which suggested that the singlet H2NC+ isomer could be formed via the corresponding triplet isomer. Also, it is shown that the reaction HCN+ + H2 might lead to this metastable isomer(More)
A data dependent peak model (DDPM) based spectrum deconvolution method was developed for analysis of high resolution LC-MS data. To construct the selected ion chromatogram (XIC), a clustering method, the density based spatial clustering of applications with noise (DBSCAN), is applied to all m/z values of an LC-MS data set to group the m/z values into each(More)
The essential features of the potential energy surface for the thermal decomposition of silane have been calculated with extended basis sets, augmented by correlation corrections. It is predicted that the transition state for the molecular elimination lies 56.9 kcal/mol above silane. For the reverse reaction, the transition state is less than 2 kcal/mol(More)
Ab initio molecular orbital theory is used to determine if the molecular ion HOC+ is linear (as are the isoelectronic species HCN, HNC, HCO+, etc.), or if it is quasilinear. Near the Hartree-Fock limit the molecule is either linear, or very close to linear. Electron correlation favors the linear geometry, leading to the unequivocal prediction of a linear(More)