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Glass formation limits were determined for the lanthanum borate glasses. Stable immiscibility prevents the formation of clear glasses over the range 0 to 20 mol% La203, but excellent quality glasses could be formed between 20 and 28 mol% La203. Data are reported for the density, refractive index, thermal expansion coefficient, glass transformation and dilatometric softening temperatures, transformation range viscosity, helium permeability, and chemical durability of these glasses. A limited Raman and infrared spectroscopy study suggests that lanthanum plays a similar structural role in these glasses and in the related crystals.

Apatites can be used as bioceramic materials for tooth and bone implants. Infrared (4000 to 400 cm−1) and laser‐Raman spectra were obtained for hydrothermally prepared hydroxyapatites with the general formula X10(PO4)6(OH)2 where X= Ca2+ Sr2+, Ba2+, or Pb2+ Fundamental vibrational modes were identified and empirical band assignments made. Analysis of the vibrational spectra led to the reassignment of the v2 mode to a higher wave‐number, lower‐intensity band (e.g. ∼470 cm−1 for Ca hydroxyapatite). Effects of solid‐state interaction were noted in the vibrational spectra and interpreted by factor‐group analysis. An “effective” factor group C6h, which neglects the locations of the OH− ions, best describes the vibrational spectra of the hydroxyapatites.

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The infrared spectra of bis(glycino) complexes of Pt II, Pd II, Cu II, and Ni II have been measured from 4000 to 250 cm−1. For cis-bis(glycino) Cu II monohydrate, the spectra have been obtained including its three deutero analogs. Normal coordinate analyses have been carried out on all these complexes using the 1:1 (metal/ligand) approximation. The results indicate that the metal—nitrogen stretching bands are located between 550 and 430 cm−1 and the metal—oxygen stretching bands are between 420 and 290 cm−1. The metal—nitrogen and metal—oxygen stretching force constants have the same value for each metal studied, and are 2.10, 2.00, 0.90, and 0.70 mdyn/Å for Pt II, Pd II, Cu II, and Ni II, respectively.