Reference

Structural data from infrared spectra of metal(II) acetate crystal hydrates

Structural data from infrared spectra of metal(II) acetate crystal hydrates. Stoilova, D.; Nikolov, G.; Balarev, Kh. (Higher Inst. Chem. Technol., Burgas, Bulg.). Izv. Khim., 9(2), 371-81 (English) 1976. CODEN: IZKHDX. DOCUMENT TYPE: Journal CA Section: 73 (Spectra by Absorption, Emission, Reflection, or Magnetic Resonance, and Other Optical Properties) The following 2 methods used thus far for detecting the type of bonding of the acetate ligand are crit. examd.: (1) the direction of the shift of .nu.as(CO) and .nu.s(CO) (Nakamoto, K., 1968); and (2) the numerical value of the difference .DELTA.Several substances like 5743-26-0 may be metioned in this study. = .nu.as(CO)-rs(CO) (Cotton, F. A., 1960). In some cases both methods give unreliable results probably due to the mixing of the COO group stretching vibrations with other vibrations of the complex. A new criterion is proposed for detecting the type of bonding of the acetate ligand. This criterion is based on the finding that unidentate acetate shows 3 bands in the 720-920 cm-1 region (probably due to COO bending vibrations .delta.(OCO)) and a strong band at about 540 cm-1 (out-of-plane COO bending vibration, .pi.(OCO)). These bands are absent if the acetate is bridged or their no. is reduced if the acetate ligand is bidentate. This new criterion is helpful if used in conjunction with the above 2 criteria. IR data for mixed crystals show that the isodimorphous substitution of the metal ion is not additive with respect to the IR spectra of the 2 metal ion acetates present in the mixed crystal. .

Assignment of symmetry-related cadmium shielding tensors to lattice positions in cadmium acetate dihydrate

Assignment of symmetry-related cadmium shielding tensors to lattice positions in cadmium acetate dihydrate. Marchetti, Paul S.; Honkonen, Robert S.; Ellis, Paul D. (Dep. Chem., Univ. South Carolina, Columbia, SC 29208, USA).Some commonly used reagents like 14336-66-4 and 5743-04-4 are used in this experiment. J. Magn. Reson., 71(2), 294-302 (English) 1987. CODEN: JOMRA4. ISSN: 0022-2364. DOCUMENT TYPE: Journal CA Section: 77 (Magnetic Phenomena) An oriented single-crystal NMR expt. was carried out for a Cd acetate dihydrate crystal having 66% 13C enrichment of the acetate carboxylate groups. The resulting 113Cd-13C direct dipole-dipole interactions give rise to an orientation-dependent modulation of 113Cd NMR linewidths for each of 4 magnetically distinguishable shielding tensors in the crystal. Comparison of obsd. Cd linewidths with those computerized as a function of crystal orientation allows for unambiguous assignment of each of the 4 symmetry-related 113Cd shielding tensors to specific lattice positions in the crystal. These assignments are in agree with those made based upon empirical rules, and serve to confirm, by means independent of previous assumptions, the reliability of the assignment rules used previously. Confirmation of the validity and reliability of such rules is essential for the accurate interpretation of Cd single-crystal NMR data in terms of shielding tensor-structure correlations to Cd chem. shifts. .