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A series of tertiary phosphine substituted alkyl- and acyltetracarbonylmanganese(I) complexes has been studied by cross-polarization and magic-angle-spinning (CP-MAS), 31P solid-state NMR spectrosc...

The 31P chemical shift anisotropies have been measured at 293 K for the triphenylphosphine ligands in solid pentacarbonyl(triphenylphosphine)chromium(0), Cr(CO)5(PPh3) (1), and cis- and trans-tetra...

The Raman spectra of the ammonia-borane complex, NH(3)BH(3), have been investigated as a function of pressure up to 40 kbar. Vibrational modes involving the NH(3) group show negative pressure dependences, supporting the existence of the dihydrogen bond, but the vibrations of the BH(3) group have a positive dependence. Two transitions were observed in the solid phase under pressure, in contrast to the temperature behavior, where a single transition occurs. Factor group splitting occurs for the degenerate vibrations, and this allows the correct assignment of the observed vibrations.

The wavenumbers of the ν(3) metal-hydrogen stretching mode (T(1u)) in the IR spectra of both ternary and quaternary hexahydrido salts of transition metals from groups 7 to 10 ([Mn(I)H(6)](5-), [Fe(II)H(6)](4-), [Ru(II)H(6)](4-), [Os(II)H(6)](4-), [Ir(III)H(6)](3-), and [Pt(IV)H(6)](2-)) depend linearly upon the ionization energies of the counterions (alkali metal, alkaline earth, and lanthanide) with a separate line for each metal. This relationship provides quantitative support for the charge-transfer mechanism for explaining the stabilities of these compounds.

The 31 P chemical shift anisotropies have been measured for solid triphenyl phosphite, P(OPh) 3 (at 128 K), and the complex with the tricarbonyl(thiocarbonyl)chromium(b) moiety, mer,trans-Cr(CO) 3 (CS) [P(OPh) 3 ] 2 (at 298 K). The shift tensor is axially symmetric in the phosphite ligand, and the major change upon complexation occurs for the components of the shift tensor perpendicular to the bond direction. The crystal structure of the chromium complex has been determined by single-crystal X-ray diffraction at 291 K. The complex crystallizes in the centric P2 1 /n (No. 14) space group with cell constants (at 20 o C) R=8.166(1) A, b=11.530(2) A, c=20.183(2) A, β=96.41(1) o , and Z=2

The Raman and infrared spectra of gas phase Re(2)O(7) are reported. The experimental vibrational spectra of molecular Tc(2)O(7) and Re(2)O(7) are compared with calculated spectra. The results of these studies agree with a nonlinear M-O-M bridge for Tc(2)O(7) and Re(2)O(7). For infrared intensity calculations, the point charge approximation is used, while for the Raman calculations a combination of bond and atom polarizabilities is adopted. Pure Re(2)O(7) was prepared from rhenium wire, but attempts to prepare it from rhenium powder and oxygen always led to infrared spectra showing serious contamination from a species containing an -OH linkage. Detailed experiments identified this molecule as HReO(4), a unique transition metal analogue of the perhalic acids, and a partial infrared spectrum of this molecule is reported.