Geoffrey Ritchie

Emeritus Professor - School of Science and Technology

Geoffrey Ritchie

Research Interests

Research in this area is concerned primarily with fundamental molecular properties (dipole moments, quadrupole moments, polarizabilities and magnetizabilities) that are derivable from experiments in which laser light is passed through fluids whose molecules are oriented by electric and magnetic fields. Experimental values of such quantities are of interest because of the information that they provide about the nature of molecular charge distributions, molecular structure and intermolecular forces; and hyperpolarizabilities, in particular, underlie the enormously important, high-technology field of non-linear optics.

Studies currently in progress include measurements of the depolarization ratio for laser light that is Rayleigh-scattered by gases; observations of the pressure and temperature dependence of the electro-optical Kerr effect, the magneto-optical Cotton-Mouton effect and the field-gradient induced birefringence effect in gases; applications of the analogous solution-phase Kerr, Cotton-Mouton and field-gradient birefringence effects; and, in collaboration with Dr M.A. Spackman, ab initio computations of relevant molecular properties.

Publications

Publications

Ritchie G.L.D. and E.W. Blanch, Temperature dependence of the electrooptical Kerr effect: Anisotropic electric dipole polarizabilities of NH3, CH3NH2, (CH3)(2)NH,and (CH3)(3)N, J. Phys. Chem. A, 107(12), pp. 2093-2099, 2003.

Ritchie G.L.D., J.N. Watson and R.I. Keir, Temperature dependence of electric field-gradient induced birefringence (Buckingham effect) and molecular quadrupole moment of N-2. Comparison of experiment and theory, Chem. Phys. Lett., 370(3-4), pp. 376-380, 2003.

Blanch E.W., R.L. Keir and G.L.D. Ritchie, Rayleigh depolarization ratios, Kerr effects, polarizabilities, and hyperpolarizabilities of CH3Br, CH2Br2,CHBr3, and CBr4. Comparison of experimental and a initio calculated polarizabilities, J. Phys. Chem. A, 106(16), pp. 4257-4262, 2002.

Couling V.W., B.W. Halliburton, R.I. Keir and G.L.D. Ritchie, Anisotropic molecular polarizabilities of HCHO, CH3CHO, and CH3COCH3. Rayleigh depolarization ratios of HCHO and CH3CHO and first and second Kerr virial coefficients of CH3COCH3, J. Phys. Chem. A, 105(17), pp. 4365-4370, 2001.

Ritchie G.L.D. and J.N. Watson, Temperature dependence of electric field-gradient induced birefringence (the Buckingham effect) in C6H6 and C6F6: comparison of electric and magnetic properties of C6H6 and C6F6, Chem. Phys. Lett., 322(3-4), pp. 143-148, 2000.

Lamb D.W. and G.L.D. Ritchie, Cotton-Mouton effect, magnetizability anisotropy and molecular charge distribution of boron trichloride (vol 310, pg 150, 1999), Chem. Phys. Lett., 317(6), pp. 653-653, 2000.

Lamb D.W. and G.L.D. Ritchie, Cotton-Mouton effect, magnetizability anisotropy and molecular charge distribution of boron trichloride, Chem. Phys. Lett., 310(1-2), pp. 150-154, 1999.

Coonan M.H. and G.L.D. Ritchie, Cotton-Mouton effect and optical-frequency molecular polarizability anisotropy of ethylene, Chem. Phys. Lett., 293(3-4), pp. 197-201, 1998.

Lamb D.W., R.I. Keir and G.L.D. Ritchie, Polarizability and magnetizability anisotropies of trimethylboroxine, Me3B3O3. Comparison of boroxine and benzene ring systems, Chem. Phys. Lett., 291(1-2), pp. 197-201, 1998.

Keir R.I. and G.L.D. Ritchie, Rayleigh depolarization ratios and molecular polarizability anisotropies of BX3 (X = F, Cl, Br, I). Comparison of experimental results and ab initio calculations, Chem. Phys. Lett., 290(4-6), pp. 409-414, 1998.

Keir R.I., D.W. Lamb, G.L.D. Ritchie and J.N. Watson, Polarizability anisotropies, magnetizability anisotropies and molecular quadrupole moments of acetylene, methylacetylene and dimethylacetylene, Chem. Phys. Lett., 279(1-2), pp. 22-28, 1997.

Watson J.N., I.E. Craven and G.L.D. Ritchie, Temperature dependence of electric field-gradient induced birefringence in carbon dioxide and carbon disulfide, Chem. Phys. Lett., 274(1-3), pp. 1-6, 1997.

Dennis G.R. and G.L.D. Ritchie, Molecular Quadrupole-Moments, Magnetic Anisotropies, and Charge-Distributions of Borazine, B-Trichloroborazine, N-Trimethylborazine, and B-Trichloro-N-Trimethylborazine - Comparison with Benzene and Its Derivatives, J. Phys. Chem., 97(32), pp. 8403-8409, 1993.

Coonan M.H. and G.L.D. Ritchie, Cotton-Mouton Effect, Magnetic-Anisotropy and Molecular Quadrupole-Moment of Acetylene, Chem. Phys. Lett., 202(3-4), pp. 237-241, 1993.

Coonan M.H., I.E. Craven, M.R. Hesling, G.L.D. Ritchie and M.A. Spackman, Anisotropic Molecular Polarizabilities, Dipole-Moments, and Quadrupole-Moments of (Ch2)2x, (Ch3)2x, and C4h4x (X = O, S, Se) - Comparison of Experimental Results and Abinitio Calculations, J. Phys. Chem., 96(18), pp. 7301-7307, 1992.