Laser Excitation Spectroscopy of the Jet-Cooled Methoxy Radical Amidst Hydroxyl Transitions

Abstract

Laser-induced fluorescence excitation spectra of the methoxy radical have been recorded under high resolution in a supersonic jet expansion. The rotational structure associated with the 3¹ ₀ band of methoxy has been identified in the midst of strong overlapping rotational transitions due to the hydroxyl radical in the 32240 - 32580 cm^?1 spectral region. Rotationally-resolved à ²A₁ – [Xtilde] ²E spectra of the 3¹ ₀ band of methoxy have been explicitly assigned using the nomenclature for prolate symmetric top transitions in doublet states.     

Remediation of environmentally hazardous organophosphates by artificial metalloenzymes

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A validated Quantitative HPTLC Method for Analysis of Biomarkers in Enicostemma littorale Blume

JPC – Journal of Planar Chromatography – Modern TLC - Enicostemma littorale (Chota-Chirayata or Mamejava) is a glabrous perennial herb belonging to the family Gentianaceae. This plant...     

Visible absorbing symmetrical squaraine and croconine dye derivatives: A comparative computational study

Visible absorbing C–N bonding squaraines (SQ1‐SQ5) and croconines (CR1‐CR5) with an increase in conjugation at donor groups and heteroaromatic donor substituents have been studied by density functional theory and time‐dependent density functional theory methodologies. In these molecules, croconines always have absorption nearly 100‐nm red shift than its corresponding squaraines (it is in consistent with C–C bonding, near infrared absorbing squaraine and croconines). The reason behind this drastic red shift, by changing the central acceptor of 4‐membered squarate ring with 5‐membered croconate ring, has been analyzed by considering the concept of diradical character and variation in central C–C–C angle. It is also observed that within the same series of molecules (either in squaraine or in croconines), with an increase in donor capacity (conjugation), absorption increases towards longer wavelength region because of destabilization of HOMO and stabilization of LUMO levels. A small blue shift was observed for heteroaromatic donor groups when compared with aromatic donor group.     

Alkoxide-induced nucleophilic trifluoromethylation using diethyl trifluoromethylphosphonate

A novel alkoxide-induced nucleophilic trifluoromethylation of carbonyl compounds, disulfides, and diselenides using diethyl trifluoromethylphosphonate is presented. In these reactions diethyl trifluoromethylphosphonate acts as a synthon.     

Visible to NIR absorbing C–N and C–C bonding squaraines: A computational study

We report a comparative computational study of 2 series of molecules with C–N bonding squaraines (NSQ) and C–C bonding squaraines (CSQ), having absorption from visible to near infrared region (350‐800 nm). The NSQ are considered as molecules with break‐in conjugation, and CSQ are considered as molecules with complete conjugation in molecular backbone. The lowest electronic excitations in CSQ molecules are always having around 200 nm red shifted absorption than its corresponding NSQ molecules. The reason for this drastic red shift in CSQ series than NSQ has been systematically studied by density functional theory, time‐dependent density functional theory, and symmetry adopted cluster configuration interaction methods. The CSQ series are showing less charge transfer than NSQ, but having small diradical character. This study may be helpful in design and synthesis of new squaraine dyes, which are useful in materials applications.     

From chaos to disorder: Statistics of the eigenfunctions of microwave cavities

We study the statistics of the experimental eigenfunctions of chaotic and disordered microwave billiards in terms of the moments of their spatial distributions, such as the inverse participation ratio (IPR) and density-density auto-correlation. A path from chaos to disorder is described in terms of increasing IPR. In the chaotic, ballistic limit, the data correspond well with universal results from random matrix theory. Deviations from universal distributions are observed due to disorder induced localization, and for the weakly disordered case the data are well-described by including finite conductance and mean free path contributions in the framework of nonlinear sigma models of supersymmetry.     

New lathyrane and podocarpane diterpenoids from Jatropha curcas

Chemical investigation on Jatropha curcas resulted in the isolation of twenty constituents among which four diterpenoids were unknown and six compounds, tetradecyl-(E)-ferulate, 3-O-(Z)-coumaroyl oleanolic acid, heudelotinone, epi-isojatrogrossidione, 2alpha-hydroxy-epi-isojatrogrossidione, and 2-methyanthraquinone had not been reported earlier from this species. The structures of the new compounds were established by extensive studies of their 1D- and 2D-NMR spectra.     

Degenerating families of rank two bundles

We construct families of rank two bundles on , in characteristic two, where for , is a sum of line bundles, and is non-split. We construct families of rank two bundles on , in characteristic , where for , is a sum of line bundles, and is non-split.