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Arthur Maki Robert L. Sams Jeffrey Barber Engelene t.H. Chrysostom Alfons Weber 《Journal of Molecular Spectroscopy》2004,225(2):109-122
Several new infrared absorption bands for 32S16O3 have been measured and analyzed. The principal bands observed were ν1+ν2 (at 1561 cm−1), ν1+ν4 (at 1594 cm−1), ν3+ν4 (at 1918 cm−1), and 3ν3 (at 4136 cm−1). Except for 3ν3, these bands are very complicated because of (a) the Coriolis coupling between ν2 and ν4, (b) the Fermi resonance between ν1 and 2ν4, (c) the Fermi resonance between ν1 and 2ν2, (d) ordinary l-type resonance that couples levels that differ by 2 in both the k and l quantum numbers, and (e) the vibrational l-type resonance between the A1′ and A2′ levels of ν3+ν4. The unraveling of the complex pattern of these bands was facilitated by a systematic approach to the understanding of the various interactions. Fortunately, previous work on the fundamentals permitted good estimates of many constants necessary to begin the assignments and the fit of the measurements. In addition, the use of hot band transitions accompanying the ν3 band was an essential aid in fitting the ν3+ν4 transitions since these could be directly observed for only one of four interacting states. From the hot band analysis we find that the A1′ vibrational level is 3.50 cm−1 above the A2′ level, i.e., r34=1.75236(7) cm−1. In the case of the 3ν3 band, the spectral analysis is straightforward and a weak Δk=±2, Δl3=±2 interaction between the l3=1 and l3=3 substates locates the latter A1′ and A2′ “ghost” states 22.55(4) cm−1 higher than the infrared accessible l3=1 E′ state. 相似文献
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硅基材料是新一代高容量锂离子蓄电池负极材料的典型代表,近年来已成为理论研究和应用研究的热点.本文介绍了锂离子电池硅基负极材料的制备方法、电化学性能及其研究现状,分析了硅材料作为锂离子电池负极材料存在的问题;讨论了硅材料作为锂离子电池负极材料的研究前景.并指出若能克服目前存在问题,将有望成为新一代锂离子电池负极材料. 相似文献
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Several organotin(IV) complexes with quadri- and terdentate anionic Schiff base ligands have been investigated in the solid state using 119Sn Mössbauer and IR spectroscopies, Mössbauer parameters derived from both zero-field and magnetically perturbed spectra suggest that the R2Sn(Salen)(R = Me, Et, Ph) and Me2Sn(Saldap-2OH) complexes have similarly distorted trans-octahedral structures. However, in Ph2Sn(HSaldap-2-O) the ligand appears to be only terdentate, leading to a penta-coordinate structure similar to those of the R2Sn(Sal-N-2-OC6H4) derivatives (R = Me, Ph). For Ph3Sn(Sal-N-2-OC6H4) the asymmetry parameter of the electric field gradient is close to unity, confirming a mer-octahedral configuration for this complex. 相似文献
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A reaction between C6F5Cl and elemental fluorine under pressure produced pentafluorophenylchlorine(III)difluoride(1) and 1,2-difluoro-1,2-bis(pentafluorophenyl)dichlorane, C6F5Cl(F)Cl(F)C6F5.The dichlorane was a stable colorless liquid with a boiling point of 121 – 123°. Its characterization by elemental analysis, IR, NMR and Mass Spectra will be presented. It is believed to be the first stable compound with a chlorine-chlorine bond and may be considered to be a derivative of the unknown Cl2F4. 相似文献
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The [Ru(bipy)(2)(1)](PF(6))(2) (bipy refers to 2,2'-bipyridine) complex, comprising a ruthenium(II) tris(2,2'-bipyridine) luminophore covalently linked to a di[(o-triethyleneglycoxy)phenyl]amine crown ether 1, has been synthesized and fully characterized. The photophysical properties of this metal complex have been examined in solution at ambient temperature. Luminescence from the metal complex is enhanced significantly in the presence of various adventitious cations, including protons. In particular, Li(+) cations bind to the crown ether, as evidenced by (1)H NMR and luminescence spectroscopy. Cation binding serves to decrease the rate of reductive quenching of the triplet state of the metal complex, thereby increasing the extent of luminescence. The solution-phase conformation of [Ru(bipy)(2)(1)](PF(6))(2), with and without encapsulated Li(+), has been examined by 2-D NMR and by molecular dynamics simulations. 相似文献
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Tunable diode laser spectra have been measured for the ν4 band of cis-HONO near 850 cm?1 and the ν2 band of rans-HONO near 1700 cm?1. The ν4 band is completely unperturbed and 355 well-resolved transitions have been fit with a standard deviation of 0.0007 cm?1. The ν2 band appears to have some small perturbations, but about 190 transitions have been fit with a standard deviation of 0.0027 cm?1. Rotational and centrifugal distortion constants are given for both bands. 相似文献
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The photophysical properties of osmium(II) bis(2,2':6',2' '-terpyridine) have been recorded over a wide temperature range. An emission band is observed and attributed to radiative decay of the lowest-energy metal-to-ligand, charge-transfer (MLCT) triplet state. This triplet is coupled to two other triplet states that lie at higher energy. The second triplet, believed to be of MLCT character, is reached by crossing a barrier of only 640 cm(-1), but the highest-energy triplet, considered to be of metal-centered (MC) character, is separated from the lowest-energy MLCT triplet by a barrier of 3500 cm(-1). Analysis of the emission spectrum shows that both low- and high-frequency modes are involved in the decay process, while weak emission is seen from the second excited triplet state. The magnitude of the low- and high-frequency modes depends on temperature in fluid solution but not in a KBr disk. Apart from a substantial lowering of the triplet energy, the photophysical properties are relatively insensitive to the presence of an ethynylene substituent at the 4' position of each terpyridine ligand. However, the barrier to reaching the MC triplet is markedly reduced, and the vibrational modes become less sensitive to changes in temperature. 相似文献