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The dependences of the nonreactive scattering of potassium atoms at thermal energies from SF6, CCl4, and SnCl4 on internal energy of the molecules and initial relative kinetic energy are studied as a function of scattering angle. The angular dependence of the nonreactive cross sections was analyzed with an optical model of chemical reactions to obtain information about potential parameters in an assumed form of two-body interaction, the threshold conditions for reaction, the probability of reaction as a function of the distance of closest approach and internal energy, as well as an estimate of the total reaction cross section. (Author), Prepared in cooperation with Massachusetts Inst. of Tech., Cambridge. Dept. of Chemistry.

The report covers the development of circulatory liquid lasers based on Nd(+3) in aprotic solvents. The static laser properties of three systems, SeOCl2:SnCl4, POCL3:SnCl4 and POCL3:ZrCl4, are presented in detail. It is shown from the point of view of gain, efficiency and loss, that the first and third systems are equivalent, while the second exhibits some degree of solubility instability. Chemically, the POCL3:ZrCl4 represents a significant improvement in that it has a much decreased toxicity and is much less chemically reactive. Finally, it is shown that the losses, while high, are not excessive for pulsed systems. Investigation of the nonlinear properties of these liquid laser materials shows that they are capable of sustaining such effects, but they are not self-focusing liquids. The nonlinear properties observed occur at high thresholds and should present no performance limitations for non-Q-switched operation. The design and operating characteristics of all the components for a circulatory laser system are described in detail, including the pump, the cell, the heat exchanger and associated tubing. In addition, the characteristics of the flash tubes, the laser head, the power supply and the energy storage unit to be used in the repetitively pulsed laser application are described. (Author)

Aprotic liquid laser solutions (Nd(+3):SeOCl2:SnCl4, Nd(+3):POCl3:SnCl4 and Nd(+3)TFA:POCl3:ZrCl4) were evaluated in terms of their spectroscopic and laser properties. The emission and absorption spectra and the transition cross section for the laser are presented and compared with those for glass. The efficiency, loss and laser output are given for various system parameters and the results compared with some values for glass in a similar experimental setup. Initial results are given for stimualted Brillouin and stimulated Raman scattering from the laser solutions. Finally, the hydrodynamic behavior of a glycerin-water solutin with a 12 centipoise viscosity (comparable to the liquid laser solutions) is described. These experiments were carried out in actual laser cells or plastic prototypes. It is shown that such circulating solutions exhibit good optical properties. (Author)