  We present multi-configuration Breit-Pauli distorted-wave photoionization
(PI) cross sections and radiative recombination (RR) and dielectronic
recombination (DR) rate coefficients for the first six krypton ions. These were
calculated with the AUTOSTRUCTURE code, using semi-relativistic radial
wavefunctions in intermediate coupling. Kr has been detected in several
planetary nebulae (PNe) and H II regions, and is a useful tracer of
neutron-capture nucleosynthesis. PI, RR, and DR data are required to accurately
correct for unobserved Kr ions in ionized nebulae, and hence to determine
elemental Kr abundances. PI cross sections have been determined for ground
configuration states of Kr^0--Kr^5+ up to 100 Rydbergs. Our Kr^+ PI
calculations were significantly improved through comparison with experimental
measurements. RR and DR rate coefficients were determined from the direct and
resonant PI cross sections at temperatures (10^1--10^7)z^2 K, where z is the
charge. We account for Delta n=0 DR core excitations, and find that DR is the
dominant recombination mechanism for all but Kr^+ at photoionized plasma
temperatures. Internal uncertainties are estimated by comparing results
computed with three different configuration-interaction expansions for each
ion, and by testing the sensitivity to variations in the orbital radial scaling
parameters. The PI cross sections are generally uncertain by 30-50% near the
ground state thresholds. Near 10^4 K, the RR rate coefficients are typically
uncertain by <10%, while those of DR exhibit uncertainties of factors of 2 to
3, due to the unknown energies of near-threshold autoionizing resonances. With
the charge transfer rate coefficients presented in the third paper of this
series, these data enable robust Kr abundance determinations in photoionized
nebulae for the first time.
