DEUTERIUM CHEMISTRY IN PROTOPLANETARY DISKS. II. THE INNER 30 AU

We present the results of models of the chemistry, including deuterium, in the inner regions of protostellar disks. We find good agreement with recent gas-phase observations of several (non-deuterated) species. We also compare our results with observations of comets and find that in the absence of other processing, e.g., in the accretion shock at the surface of the disk, or by mixing in the disk, the calculated D/H ratios in ices are higher than measured and reflect the D/H ratio set in the molecular cloud phase. Our models give quite different abundances and molecular distributions to other inner disk models because of the differences in physical conditions in the model disk. This emphasizes how changes in the assumptions about the density and temperature distribution can radically affect the results of chemical models.