Vibration reports

There is widespread interest (220) in the electronic structures of tetrahedral oxyanions of the type M04. Being quasi-isoelectronic the neutral tetroxides, M04, M = Ru, Os, are well suited for vapor-phase UPS studies (49, 102, 140) of the bonding in this type of system. Unfortunately impurities are apparent in two of these spectral studies (102, 140), and in one of them (140) doubts have been raised (49) about the validity of the reported vibrational fine structure. Furthermore, the interpretations presented in the three papers are somewhat different. Overall, the interpretation of Orchard et al. (49) appears to be the most reasonable. 

Nitromethane, CH -NOf. The equilibrium structure of singlet nitromethane has been studied at several levels of theory [3,60,64-71]. Two conformations are possible for nitromethane, staggered (Is) and eclipsed (le), but the eclipsed form has been characterized as a transition structure at MP2/6-31G with an imaginary frequency of 30 cm 1 [3]. Rotation around the H3C-NO2 bond occurs essentially without barrier the estimated value is only 0.01 kcal/mol. This is in accordance with a microwave study, which reports a C-N rotation barrier of only 6 cal/mol [72,73]. The C-N bond length of nitromethane has been estimated with X-ray single crystal diffraction [74], neutron diffraction [46,75], microwave spectroscopy [72,73], MP2/6-31G [3], and B3LYP/6-31+G [71] at respectively 1.449, 1.486, 1.489, 1.485, and 1.491 A, showing that the theoretical estimates compare very well with those determined by experimental methods. The experimentally reported vibrational frequencies of nitromethane... 

The team generates reports for two management reports. Vibration inspectors generate and distribute detailed surveillance reports to the equipment owners and the area maintenance supervisor so that corrective action can be planned. The inspectors also provide a summary report for middle management. 

We adopt the results of Spiridonov and Romanov A XX/, Xg - X - 278.7563 x 10 g cm. A normal coordinate treatment of NbBrg(g) in the Urey-Bradley force fields was performed by So (7) using the reported vibrational frequencies of Beattie and Ozin (6). This work by So (7) was Intended to check the correctness of the reported fundamental frequencies and predict those unobserved frequencies (Vg, v, Vg). Beattie and Ozin (6) had recorded the gas phase Raman spectra of niobium and tantalum chloride and bromide. We adopt the results of So (7 ) which support the work of Beattie and Ozin (6). 

MD has been used very effectively to elucidate vibrational spectra. Garofalini (1982) reported vibrational modes at 400, 800 and 1100 cm in vitreous Si02 compared to 450, 800 and 1050 cm observed in Raman and 465, 800 and 1100 cm observed in IR and 350, 800 and 1080 cm observed in inelastic neutron scattering. Experimental observation such as non-Newtonian behaviour of glass forming melts (Simmons et al., 1982), brittle fracture of Si02 (Ochoa et al., 1991) are only some of the other successful simulations using this powerful technique. 

Three groups have reported vibrational data for Hg(SMe)2 in the solid state, all of which are in agreement = 337 cm in the IR, and =... 

Under certain conditions, the preference of Hg(II) for a CN = 2 with thiolate as a ligand can be overcome, and a few simple mononuclear complexes of the formulas [Hg(SR)3j and [Hg(SR)4] have been structurally characterized. Unfortunately, only Bowmaker et al. (23) and Liesk et al. (119) have reported vibrational data. As was found with chloride compounds, the structure, and hence the vibrational spectra, of anionic Hg(II) thiolates are very cation dependent. Moreover, these studies considered only phenyl, methyl, and t-Bu derivatives, which are more dissimilar than similar. Nonetheless, the data are consistent and effectively distinguish bonding interactions (primary CN = 3,4) from secondary interactions (primary CN = 2). Based on correlation of the structurally characterized complexes and vibrational data it is not possible at this time to distinguish between three- and four-coordinate complexes on vibrational data alone. 

Spectral analysis of the various emission bands of CO allows an estimate of the vibrational energy di osal in the excited CO fragments, and Lawrence and Lee and Judge have reported vibrational energy distributions in CO(cf A, a 2 ... 

Force constants, Coriolis coupling constants, and mean amplitudes of vibration of InCl have also been calculated from previously reported vibrational data. The stretching force constants of the isoelectronic sequence are in the following order InCl < SnClg" < SbCl. ... 

All the reported vibration frequencies are in agreement with the literature [34, 36-39]. 

PrO was first studied at complete low resolution by Shenyavskaya et al. (1973). These authors reported vibrational analyses of 22 electronic transitions of PrO in the... 

Ce (Hoshina and Kuboniwa, 1971), (Nakazawa and Shionoya, 1974), (Kaplyanski and Feofilov, 1962 Ryan et al., 1974), Yb (Witzke et al., 1973)), whereas c.t. transitions do not. From this it seems probable that in the excited c.t. state the interaction between the R ion and its surroundings is stronger than in the excited 4f" 5d state. This is not unexpected. As far as we are aware nobody has ever reported vibrational fine structure for the c.t. transitions. Note also that luminescence from c.t. states has not been observed for the rare earths, whereas luminescence from 4f" 5d states is quite common (Ce, Eu ). 

Note that the zero of energy has been taken at the minimum of the potential well. It is customary, however, to report vibrational partition functions relative to the lowest vibrational level, which gives... 

Tables 8-12 show that the cross sections for energy transfer to states far removed from the initial state are reasonably large, so that large-Av or large-Aj transitions are not unlikely in H + H2 collisions. We also reported vibrational transitions with large quantum number changes for Ar + H2 at a collision temperature of 4500 in that study the initial rotational state of H2 was...

---