The near‐IR spectrum of polyethylene, polyethylene glycol, and polyvinylethyl ether have been measured. The CH and OH stretch and bend absorptions have been assigned using local mode theory. The CH stretch anharmonicities are about 57 cm−1, typical of CH anharmonicities in molecular samples. The CH bend anharmonicities are 7, 10, and 11 cm−1, respectively, for polyethylene, polyethylene glycol, and polyvinylethyl ether. The CH bend absorption intensities decrease by about a factor of 4 allowing these bending transitions to be observed up to the fourth overtone transition. © 1996 John Wiley & Sons, Inc.

Models were proposed for the Na-X and Na-Y zeolites with four clusters containing up to 37 atoms. The electronic structure of this model was studied by the CNDO/2 method. Charge densities on individual atoms forming the zeolite skeleton for various Si:Al ratios were calculated. The type of coordination of the Na atom in the zeolite skeleton and the character of the bonding of the Na atoms in the skeleton were also studied.

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