Diatomics-in-molecules theory applied to the Li3 molecule leads to the prediction of two forms stable with respect to Li2(1Σg+) + Li(2S) : a bent 2A1 state with an atomization energy at 0°K of 32.74 kcal/mole and an ionization energy of about 111 kcal/mole; a strongly bent 2B2 state with an atomization energy at 0°K of 30.34 kcal/mole. Potential-energy surfaces and fundamental vibrational frequencies are predicted for both states. Characteristics of the less stable linear conformation are discussed and compared with H3.

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The EPR spectrum of the ·CH2COO− radical in a single crystal host displays nonadiabatic motional effects. A phenomenological theory is suggested, based on the density matrix of the spin system, and a technique is described for rapid calculation of simulated spectra.

A reverse phase liquid chromatographic (LC) method has been developed for the assay of calcium pantothenate in commercial multivitamin tablet formulations and raw materials. The assay was validated according to the Pharmaceutical Manufacturers Association Quality Control HPLC Committee guidelines. The chromatographic system includes a C-18 column and a mobile phase consisting of 0.25M sodium phosphate buffer, pH 2.5, and acetonitrile (97 + 3 v/v). The column effluent is monitored by UV detection at 205 nm. The sample preparation involves only extraction in water followed by filtration. The method is stability-indicating with a detection limit of approximately 50 ng/mL of the calcium pantothenate in the samples. The system is linear from at least 0.02 to 0.10 mg/mL. The mean recovery of spiked placebos ranged from 98.7 to 99.8%. The within-day precision of the assay on finished products (N = 6) ranged from 0.3 to 2.0% CV. A system suitability criterion for resolution is based on the separation between calcium pantothenate and 2 closely eluting compounds, saccharin and a saccharin degradation product, 2-sulfamoylbenzoic acid.

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