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The stoichiometry-dependent optical properties of bulk samples of TiCx have been determined for four samples in the range 0.64≤x≤0.90. Reflectance and absorptance data taken in the range 0.1-30 eV have been Kramers-Kronig analyzed to obtain the dielectric function and related functions. Interband absorption begins at 0.1 eV or less. The observed interband transitions are interpreted on the basis of existing energy-band calculations. Comparison of optical structure with joint-density-of-states calculations shows that the rigidband model cannot be applied strictly to explain the x-dependent structure, especially in the 5-10 eV region. The electron-energy-loss functions exhibit two peaks, one near the free-electron plasmon energy and one near 10 eV, both peaks shifting to higher energy as x increases.

Photoemission studies {12(hv(135eV) of room-temperature formation of the Si-Cr interface show reactive behavior with atomic intermixing and dramatic modifications of the metal-derived d density of states. Self-consistent augmented-spherical-wave calculations of the total and I-projected densities of states for the silicides Cr3Si, CrSi, and CrSi3 in simplified cubic lattice structures allow an identification of general trends in the electronic structure upon Si-Cr heteropolar bond formation. These experimental and theoretical results suggest an interface morphology where a Si-rich intermixed phase is present for a depth of =10 monolayers between the Si crystal and the unreacted Cr film. Evidence of Si segregation in the top layers of the Cr film is provided.