Simple hydrogen-bearing molecules in translucent molecular clouds
  We demonstrate relations between column densities of simple molecules: CH,
CH$^{+}$, H$_{2}$ and OH. The H$_{2}$, CH and OH molecules seem to occupy the
same environments because of tight relations between their column densities. In
contrary to this CH$^{+}$ column density does not correlate with those of other
simple molecules.
