Marvin C. Tobin

Selection Rules for Normal Modes of Chain Molecules

The selection rules for chain molecules are derived on the basis of the theory of one‐dimensional space groups. The selection rules for crystals of polymer chains are discussed and correlated with those of isolated chains. The polyethylene molecule is analyzed in detail by these methods and the predictions of the theory compared with experiment. The effects of perturbations on the spectra are discussed.

The Vibrational Spectra and Structure of Nitrogen Tetrasulfide

The infrared and Raman spectra of nitrogen tetrasulfide (N4S4) are presented along with the infrared spectrum of nitrogen hydrogen sulfide (N4S4H4). These data have been considered in terms of the several proposed structures for nitrogen tetrasulfide and have been found to be consistent with a cage structure of D2d symmetry. With the aid of a normal coordinate analysis of the nondegenerate symmetry species, a complete assignment of frequencies to their normal modes of vibration has been made for nitrogen tetrasulphide. A tentative assignment of frequencies is also given for nitrogen hydrogen sulfide.

Electrical Properties of Single Crystals of Pyrene—Tetracyanoethylene Charge‐Transfer Complex

Transient photocurrents injected with a microsecond light flash and steady‐state currents with an illuminated electrode are reported for large single crystals of pyrene—TCNE. Charge‐carrier mobilities are calculated at a series of temperatures from the transient measurements. Hole mobilities at room temperature were as high as 30 cm2/V·sec. Electron mobilities were about three orders of magnitude lower. The hole mobility appeared to have a large activation energy—about 0.5 eV.