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The electron affinity of lanthanum has been measured using laser photoelectron energy spectroscopy. This is the first electron affinity measurement for lanthanum and one of the first measurements of an electron affinity of a rare-earth series element. The electron affinity of lanthanum was measured to be 0.47 ± 0.02 eV. At least one bound excited state of La − was also observed in the photoelectron spectra, and the binding energy relative to the ground state of lanthanum was measured as 0.17 ± 0.02 eV. The present experimental measurements are compared to a recent calculation.

The electron affinity of cerium has been measured using laser photodetachment electron spectroscopy. The electron affinity of Ce(1G4) was determined to be 0.955 +/- 0.026 eV. The data also show that Ce- has at least two bound excited states with binding energies of 0.921 +/- 0.025 eV and 0.819 +/- 0.027 eV relative to the (1G4) ground state of the cerium atom. The present experimental measurements are compared to recent calculations of the energy levels of Ce-. Strong disagreement with the most recent theoretical atomic structure calculations highlights the complicated nature of this particular lanthanide.

High‐pressure Fourier‐transform infrared absorption spectroscopy was used to study poly(methyl methacrylate) in a diamond anvil cell at pressures up to ≈8 GPa. The positions of the vibrational modes were measured as a function of pressure. The data were analyzed to determine mode Grüneisen parameters and bond anharmonicities. The vibrational modes were analyzed using models that include both volume independent and dependent Grüneisen parameters, and the different models were compared. The vibrational frequency shifts as a function of pressure were found to be consistent with those measured for similar types of bonds in other molecules. This data may find applications where polymers are subjected to large pressures, including shock compression experiments. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 358–367, 2007

High‐pressure Fourier‐transform infrared absorption spectroscopy has been performed on polycarbonate, using a diamond anvil cell to produce pressures up to ∼6 GPa. The frequencies of the vibrational modes have been measured as a function of pressure. Individual mode Grüneisen parameters have been determined for six vibrational modes. The data were fit to models that included both volume‐dependent and ‐independent Grüneisen parameters. The vibrational frequency shifts as a function of pressure have been found to be consistent with those measured for similar types of bonds in other molecules. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 734–742, 2008