Studies on Simulation of Spectra of Some Organic Compounds

Quantum chemical viz. ab initio or semi-empirical based simulation studies are now prevailing among workers / scientists pursuing their studies in theoretical chemistry. These studies provide better insight for the compounds so far as the studies of their structural orother parameters are concern. Studies involving the packages developed on the basis of ab-initio or semi-empirical methods are proven to be more effective and as a better tool because of number of their advantages. The present communication includes the studies on synthesis or procurement along with the simulation of spectra viz. I.R. of some heterocyclic organic compounds.

Simulation of Spectra Code (SOS) for ITER Active Beam Spectroscopy

The concept and structure of the Simulation of Spectra (SOS) code is described starting with an introduction to the physics background of the project and the development of a simulation tool enabling the modeling of charge-exchange recombination spectroscopy (CXRS) and associated passive background spectra observed in hot fusion plasmas. The generic structure of the code implies its general applicability to any fusion device, the development is indeed based on over two decades of spectroscopic observations and validation of derived plasma data. Four main types of active spectra are addressed in SOS. The first type represents thermal low-Z impurity ions and the associated spectral background. The second type of spectra represent slowing-down high energy ions created from either thermo-nuclear fusion reactions or ions from injected high energy neutral beams. Two other modules are dedicated to CXRS spectra representing bulk plasma ions (H+, D+, or T+) and beam emission spectroscopy (BES) or Motional Stark Effect (MSE) spectrum appearing in the same spectral range. The main part of the paper describes the physics background for the underlying emission processes: active and passive CXRS emission, continuum radiation, edge line emission, halo and plume effect, or finally the charge exchange (CX) cross-section effects on line shapes. The description is summarized by modeling the fast ions emissions, e.g., either of the α particles of the fusion reaction or of the beam ions itself.

Analysis of 1H and 13C{1H} NMR Spectral Parameters of Diphenylchloroarsine, Diphenylcyanoarsine, and 10-Chloro- 5,10-Dihydrophenarsazine: Identification of the Compounds through Reference to Simulated Spectra

The 1H and 13C{1H} nuclear magnetic resonance (NMR) spectra of diphenylchloroarsine, diphenylcyanoarsine, and 10-chloro-5,10-dihydrophenarsazine were recorded from samples prepared in CDCl3, CD2Cl2, and (CD3)2CO. Spectra were analyzed, and detailed 1H NMR spectral parameters were determined by iterative analysis. Simulation of spectra and their use as reference spectra for identification of the compounds under different conditions are discussed.

Spectroscopic investigations of hydrogen bonding interactions in the gas phase. IX. Vibrational satellites in the rotational spectrum of the hydrogen-bonded homodimer HCN • • • HCN

The rotational spectrum of the hydrogen cyanide dimer has been observed in the frequency range 26-40 GHz by using a Stark-modulated microwave spectrometer. Although the spectrum is very weak, even under optimum conditions, it has been possible to assign vibrational satellites in the v β progression based on the ground state and in the v β progression based on v σ ═ 1 with the aid of the computer simulation of spectra and the ground-state spectroscopic constants. The spectroscopic constants now available for the hydrogen cyanide dimerare summarized as follows: (HC 14 N) 2 (DC 14 N) 2 (HC 15 N) 2 v β ═ 1 ← 0/cm -1 35±5 30±5 35±5 v σ ═ 1 ← 0/cm -1 101 ─ ─ B o /MHz 1745.80973(50) 1661.18(26) 1684.28825(25) D J /kHz 2.133(30) (1.873) 1.900(30) r c. m ./nm 44.496 ─ 44.499 K σ /(Nm -1 ) 8.14 ─ 8.51 α β /MHz ─20.07 (2) ─17.73 (27) ─18.74 (9) γ β /MHz 0.266 (4) 0.242 (36) 0.250 (17) q β /MHz 5.33 (4) 5.44 (13) 5.15 (10) α σ /MHz (31.44) ─ ─