Variable-temperature and -pressure vibrational spectra of o-carborane

Abstract

efg tensor exactly coincide with the molecular coordinate system of Figure 1. In the more detailed SCCEHMO calculations they almost coincide.The absolute values of calculated quadrupole splittings for the [II,II] and [II,III] ions are in very good agreement with the observed data (Table III). We notice that the largest efg component is still Vyy, i.e. the component within the pyrazine plane perpendicular to the Ru-N(bridge) direction. The sign of the efg cannot be determined from powder spectra unless the triplet structure of the two components of the spectrum is resolved or, at least, manifests itself in visible asymmetries of the pattern. Such asymmetries begin to become noticeable when the splitting A of the excited state exceeds about 0.5 mm s'1. For [II,II] it is impossible to even guess the sign, while the [II,III] and [III,III] species are just at the limit where the sign of Vyy should become detectable. Owing to additional complications such as axially nonsymmetric efg tensors, unknown preferred orientation of the crystallites in the sample, and anisotropies of the Debye-Waller factor, we have to refrain from drawing any conclusions about

The electronic structure of 1,2-PCB10H11 molecular films: a precursor to a novel semiconductor

“…This is expected as the distortion of the cage by the polyhedral phosphorus is signifi cant. A somewhat similar effect is also observed for the various υ(B-H) stretch modes of 1,2-C 2 B 10 H 12 resulting in a number of closely lying vibrational bands between 2559 to 2623 cm −1 [54][55][56]. The strong bending δ (HCB) mode 1120 cm −1 observed for 1,2-PCB 10 H 11 has a similar loss energy of about 1140 cm −1 for 1,2-C 2 B 10 H 12 [54][55][56].…”

“…A somewhat similar effect is also observed for the various υ(B-H) stretch modes of 1,2-C 2 B 10 H 12 resulting in a number of closely lying vibrational bands between 2559 to 2623 cm −1 [54][55][56]. The strong bending δ (HCB) mode 1120 cm −1 observed for 1,2-PCB 10 H 11 has a similar loss energy of about 1140 cm −1 for 1,2-C 2 B 10 H 12 [54][55][56]. Similarly, the υ(C-H) stretch mode observed at 3040 cm −1 for 1,2-PCB 10 H 11 has its counterpart at about 3064 cm −1 for 1,2-C 2 B 10 H 12 [54][55][56].…”

“…The strong bending δ (HCB) mode 1120 cm −1 observed for 1,2-PCB 10 H 11 has a similar loss energy of about 1140 cm −1 for 1,2-C 2 B 10 H 12 [54][55][56]. Similarly, the υ(C-H) stretch mode observed at 3040 cm −1 for 1,2-PCB 10 H 11 has its counterpart at about 3064 cm −1 for 1,2-C 2 B 10 H 12 [54][55][56].…”

High‐pressure micro‐Raman spectra of potassium hexabromostannate(IV), K2SnBr6

“…Recently, we reported the coupling of a high-pressure, diamond-anvil cell (DAC) to a micro-Raman spectrometer and demonstrated that this arrangement is an extremely useful way of examining the pressure dependence of the phase transitions occurring in inorganic crystals such as Hg(CN),8 and o-BloC2H12 . 9 In this work, we have extended our high-pressure/micro-Raman approach to K,SnBr, . We were interested in two things: the possibility that a third phase transition be induced by the application of high pressure and the determination of the pressure dependences of the vibrational modes.…”

Carbon‐Enriched Amorphous Hydrogenated Boron Carbide Films for Very‐Low‐k Interlayer Dielectrics

“…In the CH stretch region (Figure b), the peak at ≈3070 cm −1 is assigned to the intraicosahedral CH group within the carborane molecule, and is the dominant peak for the film grown without added CH 4 . Peaks between 2800 and 3000 cm −1 are assigned to extraicosahedral hydrocarbon sp 3 CH stretching modes.…”