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Horný L Petraco ND Pak C Schaefer HF 《Journal of the American Chemical Society》2002,124(20):5861-5864
The optimized geometries, adiabatic electron affinities, and IR-active vibrational frequencies have been predicted for the long linear carbon chains HC(2n)H. The B3LYP density functional combined with the DZP basis set was used in this theoretical study. The computed physical properties are discussed. The predicted electron affinities form a remarkably regular sequence: 1.78 (HC(12)H), 2.08 (HC(14)H), 2.32 (HC(16)H), 2.53 (HC(18)H), 2.69 (HC(20)H), 2.83 (HC(22)H), and 2.95 eV (HC(24)H). The predicted structures display an alternating triple and very short single bond pattern, with the degree of bond alternation significantly less for the radical anions. 相似文献
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Odd carbon long linear chains HC2n+1H (n = 4-11): properties of the neutrals and radical anions 总被引:1,自引:0,他引:1
Horný L Petraco ND Schaefer III HF 《Journal of the American Chemical Society》2002,124(49):14716-14720
The optimized geometries, adiabatic electron affinities, vertical electron affinities, vertical electron detachment energies (for the anions), and IR-active vibrational frequencies have been predicted for the long linear carbon chains HC(2)(n)()(+1)H (n = 4-11). The B3LYP density functional combined with DZP and TZ2P basis sets was used in this theoretical study. These methods have been extensively calibrated versus experiment for the prediction of electron affinities (Chem. Rev. 2002, 102, 231). The computed physical properties are discussed and compared with the even carbon chains HC(2)(n)()H. The predicted electron affinities form a remarkably regular sequence: 2.12 eV (HC(9)H), 2.42 eV (HC(11)H), 2.66 eV (HC(13)H), 2.85 eV (HC(15)H), 3.01 eV (HC(17)H), 3.14 eV (HC(19)H), 3.25 eV (HC(21)H), and 3.35 eV (HC(23)H). These electron affinities are as much as 0.4 eV higher than those for analogous even carbon chains. The predicted structures display an intermediate cumulene-polyacetylene type of bonding, with the inner carbons appearing cumulenic and the outer carbons polyacetylenic. 相似文献
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Analysis of a TE011 mode composite sapphire-rutile dielectric resonator has been carried out to study the temperature variation of resonance
frequency, close to the Cs atomic clock hyperfine frequency of 9.192 GHz. The complementary behavior of dielectric permittivity
with temperature of the composite has been exploited to obtain the desired turning point in the resonant frequency. The frequency
of the composite structure is found to be independent of the shield diameter beyond four times the puck diameter. 相似文献
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Determination of elemental fingerprint profile of 40 commercial beer samples was performed using inductively coupled plasma–mass
spectrometry combined with principal component analysis and receiver operating characteristic (ROC) analysis. Fourteen trace
elements, 51V, 52Cr, 59Co, 60Ni, 75As, 82Se, 95Mo, 111Cd, 115In, 121Sb, 133Cs, 208Pb, 209Bi, and 238U, were monitored. All 40 beer samples are distinguishable by using the proposed method. ROC analysis showed that individual
beer samples can be correctly identified via the magnitude of its correlation coefficient with respect to the other beers
with low false positive rate. The obtained results suggested that the elemental fingerprint technique is feasible for sample
differentiation and comparison. 相似文献
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MVN Murthy Urjit A Yajnik KRS Balaji G Bhattacharyya Amol Dighe Shashikant Dugad ND Hari Dass PK Kabir Kamales Kar D Indumathi John G Learned Debasish Majumdar NK Mondal MVN Murthy SN Nayak Sandip Pakvasa Amitava Raychaudhuri RS Raghavan G Rajasekaran R Ramachandran Alak K Ray Asim K Ray Saurabh Rindani HS Sharatchandra Rahul Sinha Nita Sinha S Umasankar Urjit A Yajnik 《Pramana》2000,55(1-2):347-355
We have identified some important and worthwhile physics opportunities with a possible neutrino detector located in India.
Particular emphasis is placed on the geographical advantage with a stress on the complimentary aspects with respect to other
neutrino detectors already in operation. 相似文献
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Josef Paldus Xiangzhu Li Nicholas D.K. Petraco 《Journal of mathematical chemistry》2004,35(3):215-251
The explicit expressions for the recently formulated general-model-space (GMS) version of the multireference state-universal (SU) coupled-cluster (CC) method [X. Li and J. Paldus, J. Chem. Phys. 119 (2003) 5320], truncated at the level of single (S) and double (D) excitations, are re-derived using the spin-orbital form of the diagrammatic technique. The focus is on the so-called coupling coefficients, which represent a new type of quantity that does not appear in the single-reference CC approaches. The role of the connectivity conditions, referred to as the C-conditions, in the elimination of disconnected terms in the GMS SU CC method is analyzed in terms of the connectivity of the resulting diagrams and is illustrated on typical examples. 相似文献
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