The GRAINS thermodynamic and kinetic code for modeling nebular condensation

The GRAINS thermodynamic and kinetic code for modeling condensation and grain growth in the solar nebula is described. The code calculates CWPI-type (Condensation With Partial Isolation) equilibrium partitioning of 33 chemical elements among 242 gaseous and 520 condensed phases, and growth in the nebula of metal and olivine grains by condensation from the nebular gas accompanied by diffusional redistribution of major and trace elements in those grains. Several examples of the GRAINS application to cosmochemical problems are briefly discussed.