  We present consistent modelling of line and continuum IR spectra in the
region close to the Galactic center. The models account for the coupled effect
of shocks and photoionization from an external source. The results show that
the shock velocities range between 65 and 80 km/s, the pre-shock densities
between 1 cm-3 in the ISM to 200 cm-3 in the filamentary structures. The
pre-shock magnetic field increases from 5. 10^{-6} gauss in the surrounding ISM
to ~8. 10^{-5} gauss in the Arched Filaments. The stellar temperatures are
~38000 K in the Quintuplet cluster and ~27000 K in the Arches Cluster. The
ionization parameter is relatively low (<0.01) with the highest values near the
clusters, reaching a maximum >0.01 near the Arches Cluster. Depletion from the
gaseous phase of Si is found throughout the whole observed region, indicating
the presence of silicate dust. Grains including iron, are concentrated
throughout the Arched Filaments. The modelling of the continuum SED in the IR
range, indicates that a component of dust at temperatures of ~100-200 K is
present in the central region of the Galaxy. Radio emission appears to be
thermal bremsstrahlung in the E2-W1 filaments crossing strip, however a
synchrotron component is not excluded. More data are necessary to resolve this
questions.
