Principles of time resolved cars studies of molecular solids

Recent studies of vibrational phase and population relaxation in molecular crystals at liquid helium temperatures are discussed. The technique of coherent antiStokes Raman scattering is becoming the method of choice for very high resolution Raman spectroscopy in those systems, so the important aspects of both time and frequency resolved CARS measurements are discussed in this article. In addition, the contributions to the residual low temperature vibron linewidth are systematically explored, drawing on experimental observations in crystalline N2, H2, benzene and naphthalene as examples. These observations are then brought into relation with current theories of exciton dynamics in condensed molecular systems. An important conclusion from these studies is the vibrational population relaxation rates show a high degree of mode selectivity, which has an impact on theories of chemical reaction dynamics. A qualitative, but detailed discussion of the mechanisms of trapping vibrational excitations by isotopic impurities is also presented

Nonlinear materials for frequency conversion

Two figures of merit, the threshold power (P/sub th/) and the limiting volume (V/sub min/) can be used to compare the relative efficiency and economy of new harmonic generating crystals. The properties of barium metaborate and L-Arginine phosphate are used to illustrate the effect of nonlinearity, birefringence, and damage threshold on these figures of merit

Non-DNA Methods for Biological Signatures

Schaldach CM, deYoreo JJ, Esposito A, et al. Non-DNA Methods for Biological Signatures. In: Breeze RG, Budowle B, Schutzer SE, eds. Microbial Forensics. Elsevier Academic Press. Burlington; In Press: 262-295