  Neutral nickel (Ni I) is abundant in the solar atmosphere and is one of the
important elements that contribute to the emission and absorption of radiation
in the spectral range between 1900 and 3900 A. Previously, the Solar Radiation
Physical Modeling (SRPM) models of the solar atmosphere considered only few
levels of this species. Here we improve the Ni I atomic model by taking into
account 61 levels and 490 spectral lines. We compute the populations of these
levels in full NLTE using the SRPM code and compare the resulting emerging
spectrum with observations. The present atomic model improves significantly the
calculation of the solar spectral irradiance at near-UV wavelengths that are
important for Earth atmo spheric studies, and particularly for ozone chemistry.
