Polymer chain orientation in tensile-stretched poly(ethylene oxide)-lithium trifluoromethanesulfonate polymer electrolytes are investigated with polarized infrared spectroscopy as a function of the degree of strain and salt composition (ether oxygen atom to lithium ion ratios of 20:1, 15:1, and 10:1). The 1359 and 1352 cm-1 bands are used to probe the crystalline PEO and P(EO)3LiCF3SO3 domains, respectively, allowing a direct comparison of chain orientation for the two phases. Two-dimensional correlation FT-IR spectroscopy indicates that the two crystalline domains align at the same rate as the polymer electrolytes are stretched. Quantitative measurements of polymer chain orientation obtained through dichroic infrared spectroscopy show that chain orientation predominantly occurs between strain values of 150% and 250%, regardless of salt composition investigated. There are few changes in chain orientation for either phase when the films are further elongated to a strain of 300%; however, the PEO domains are slightly more oriented at the high strain values. The spectroscopic data are consistent with stretching-induced melt-recrystallization of the unoriented crystalline domains in the solution-cast polymer films. Stretching the films pulls polymer chains from the crystalline domains, which subsequently recrystallize with the polymer helices parallel to the stretch direction. If lithium ion conduction in crystalline polymer electrolytes is viewed as consisting of two major components (facile intra-chain lithium ion conduction and slow helix-to-helix inter-grain hopping), then alignment of the polymer helices will affect the ion conduction pathways for these materials by reducing the number of inter-grain hops required to migrate through the polymer electrolyte.

On the photographic plates of the CO2 spectrum made by S. Mrozowski from the 30-foot, 30,000 lines per inch, Chicago grating, were found pictures of the first negative bands and the comet tail bands of CO + in which the 2 S spin splittings were resolved. From the 2 2-> 2 2 transition, the absolute differences of the spin doubling coefficients were measured. The absolute values of y 0 " and y\' for the lowest 2 S state were measured from the 2 II-* 2 S transition, and their algebraic signs determined by consideration of relative intensities of branches. Thus the signs and values of the spin doubling coefficients of 2 2' for v' -O to 4, and of 2 2" for v" = 0 to 7 have been determined.

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Pankhurst has described a band spectrum believed by him to belong to an oxide of silicon, possibly SiC>2. A better excitation of the same bands has been obtained from a similar source (a high voltage uncondensed discharge through a constriction in a quartz tube), but in helium gas instead of hydrogen. These bands have been photographed on the 30-foot, 30,000 lines per inch Chicago grating spectrograph. A band near X3840 has been resolved in the first and second orders and found to be a (0,0) transition, overlapped by a weak (1,1) transition, of the type 2 S-* 2 2, having the constants i/(0,0) =26,015.05 cm" 1 , Bo^OJlSOcnr 1 , B 0 " = 0.7253 cm" 1 , Kl,1) =25,991.44 cm"Bi' = 0.704 cm" 1 , 5i" = 0.712 cm" 1 .The coefficients of the spin doubling for the two states are YO'= +0.012 cm -1 , y 0 "= +0.002 or Yo" = +0.022 cm -1 , the value of YO" not certainly fixed as between these two alternatives. The doublet structure and the B values prove that the emitter is SiO + . Other bands at X4270 have been resolved with weak intensity and tentatively ascribed to SiC>2.