Finite-element modeling of diamond deformation at multimegabar pressures

Finite-element modeling calculations reveal the origin of the remarkably la rge elastic strains in diamond observed in recent experiments at multimegab ar pressures. This approach provides a means to determine the pressure depe ndence of the yield strength of strong materials used in the gasket, and al lows us to examine quantities that are not accessible experimentally such a s the stress and strain relations in diamond. Stress tensor elements are ob tained near the tip where large modifications in the optical properties of diamond have been observed. (C) 1999 American Institute of Physics. [S0003- 6951(99)02505-X].