  The optical properties of C$_{60}$ single crystals, intercalated with
nitrogen molecules, were investigated by the spectral-luminescence method in
the temperature range 20 - 230 K. The saturation was carried out under the
pressure of 30 atm. of N$_{2}$ at various temperatures ranging from 200 to
550$^{\circ}$C. For the C$_{60}+$N$_{2}$ system, the presence of a temperature
boundary of the adsorption crossover of about 420$^{\circ}$C was established
(transition from the diffusion mechanism of intercalation - physisorption, to
chemical interaction - chemisorption). The temperature dependence of the
integrated radiation intensity of a new nitrogen-containing substance based on
the C$_{60}$ fullerite has been recorded for the first time. Quenching of
photoluminescence at low temperatures was found. The observed new effect of
low-temperature quenching of photoluminescence is explained by the appearance
in the process of chemical interaction between the N$_{2}$ impurity molecules
and the C$_{60}$ matrix of effective exciton trapping centers and nonradiative
deactivation of electronic excitation.
