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21.
A. Baldacci V. Malathy Devi Da-Wun Chen K. Narahari Rao B. Fridovich 《Journal of Molecular Spectroscopy》1978,70(1):143-159
The absorption spectrum of carbon dioxide has been recorded in the wavenumber region 2395-2216 cm?1 with a spectral resolution between 0.02 and 0.03 cm?1. About twenty transitions have been identified and the molecular constants of the levels involved have been evaluated. In view of the interest of this region in atmospheric studies a map of the entire spectrum recorded by using a normal sample of carbon dioxide is presented including the identifications for the different bands. About 90% of the lines observed have been interpreted. Some of them have been assigned to transitions originating from higher excited states of 12C16O2 not considered before in interpreting this spectral region. For the first time, bands of 12C16O17O have been identified in the 4.3-μm spectra obtained with the natural sample. 相似文献
22.
The rotational structure of the ν1, ν3, 2ν2, ν1 + ν2, and ν2 + ν3 bands of water vapor has been recorded using a high resolution vacuum infrared spectrograph. Values for the energy levels of the ground vibrational state and of the upper states of these bands have been determined. Several intensity anomalies have been observed in lines previously assigned to the ν1, ν3, and 2ν2 bands. Experimental results for these intensity anomalies have been presented. 相似文献
23.
Stephen C. Hurlock K.Narahari Rao Lawrence A. Weller Peter K.L. Yin 《Journal of Molecular Spectroscopy》1973,48(2):372-394
The ν2 band of 14N16O2 near 13.3 μm has been measured under high resolution using a vacuum grating spectrograph equipped with a liquid helium cooled Ge:Cu detector. Over 750 transitions were identified. Analysis of the band, combined with previous work at shorter wavelengths, led to modified constants for the ground state, (0, 0, 0), and new values for the constants of the upper state, (0, 1, 0). The new constants reproduced 272 nonzero-weighted transitions with a standard deviation of 0.011 cm?1 and reproduced 346 ground state combination differences with a standard deviation of 0.010 cm?1. The spin-rotation line splittings which were observed were described satisfactorily using existing formulations. 相似文献
24.
Several vibration rotation bands of the H12C14N16O molecule have been studied by using high resolution vacuum grating infrared spectrographs. A linear molecular model has been used in establishing the vibrational assignments and evaluating the molecular constants. A value of 224.101 cm?1 has been determined for the band center of the ν5 fundamental by application of the Ritz combination principle. Future efforts will be directed to arriving at a similar result for the ν4 fundamental. 相似文献
25.
Stephen C. Hurlock Walter J. Lafferty K. Narahari Rao 《Journal of Molecular Spectroscopy》1974,50(1-3)
The rotational structure of the ν3 fundamental of 14N16O2 has been recorded by employing a vacuum grating infrared spectrograph. The analysis has led to the assignment of over 500 R- and P-branch transitions in the spectral region 1562–1650 cm−1. Molecular constants for the upper state, 001, have been presented. No Q-branch transitions were used in the evaluation of these constants. The presently obtained
and the band center ν0 = 1616.846 cm−1 differ significantly from previous determinations. Spin splitting was observed but no information was extracted about upper state spin splitting parameters. 相似文献
26.
Quantum chemistry calculations reveal that the subtle pi-pi interactions, usually in the range 2-4 kcal/mol, will become substantially significant, from 6 to 17 kcal/mol, in the presence of metal ion. The metal ions have higher affinity toward a pi-pi dimer compared to a single pi-moiety. Considering the widespread occurrence of cation-pi-pi motifs in chemistry and biology, as evident from the database analysis, we propose that the two key noncovalent forces, which govern the macromolecular structure, cation-pi and pi-pi, work in concert. 相似文献
27.
Ilyas Suhaib Umer Pendyala Rajashekhar Narahari Marneni 《Journal of Thermal Analysis and Calorimetry》2019,135(2):1197-1209
Journal of Thermal Analysis and Calorimetry - The carbon nanotubes are considered as one of the highest thermal conductive material which is having a variety of heat transfer applications. The... 相似文献
28.
MP2(FULL)/6-311++G** calculations are performed on the cation-pi complexes of Li+ and Mg2+ with the pi-face of linear (ethylene, butadiene, hexatriene, and octatetraene) and cyclic (benzene, naphthalene, anthracene, phenanthrene and naphthacene) unsaturated hydrocarbons. The interaction energy is found to increase systematically as the size of the pi-system increases. The higher interaction energy is in good correlation with the extent of charge transfer. The increase in the interaction energy is more dramatic in the case of acyclic systems. The computations reveal that larger pi-systems tend to have higher complexation energy with the metal ions, which will have important implications in our understanding of the structural and functional aspects of metal binding. 相似文献
29.
Bhaskar Sharma Y. Indra Neela G. Narahari Sastry 《Journal of computational chemistry》2016,37(11):992-1004
Quantum chemical calculations have been performed at CCSD(T)/def2‐TZVP level to investigate the strength and nature of interactions of ammonia (NH3), water (H2O), and benzene (C6H6) with various metal ions and validated with the available experimental results. For all the considered metal ions, a preference for C6H6 is observed for dicationic ions whereas the monocationic ions prefer to bind with NH3. Density Functional Theory–Symmetry Adapted Perturbation Theory (DFT‐SAPT) analysis has been employed at PBE0AC/def2‐TZVP level on these complexes (closed shell), to understand the various energy terms contributing to binding energy (BE). The DFT‐SAPT result shows that for the metal ion complexes with H2O electrostatic component is the major contributor to the BE whereas, for C6H6 complexes polarization component is dominant, except in the case of alkali metal ion complexes. However, in case of NH3 complexes, electrostatic component is dominant for s‐block metal ions, whereas, for the d and p‐block metal ion complexes both electrostatic and polarization components are important. The geometry (M+–N and M+–O distance for NH3 and H2O complexes respectively, and cation–π distance for C6H6 complexes) for the alkali and alkaline earth metal ion complexes increases down the group. Natural population analysis performed on NH3, H2O, and C6H6 complexes shows that the charge transfer to metal ions is higher in case of C6H6 complexes. © 2016 Wiley Periodicals, Inc. 相似文献
30.