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We observed OH, H$_2$O, HN$_3$, C$^{18}$O, and C$_I$ towards the +50 km/scloud (M-0.02-0.07), the CND and the +20 km/s (M-0.13-0.08) cloud in the Sgr Acomplex with the VLA, Odin and SEST. Strong OH absorption, H$_2$O emission andabsorption lines were seen at all three positions. Strong C$^{18}$O emissionswere seen towards the +50 and +20 km/s clouds. The CND is rich in H$_2$O andOH, and these abundances are considerably higher than in the surroundingclouds, indicating that shocks, star formation and clump collisions prevail inthose objects. A comparison with the literature reveals that it is likely thatPDR chemistry including grain surface reactions, and perhaps also theinfluences of shocks has led to the observed abundances of the observedmolecular species studied here. In the redward high-velocity line wings of boththe +50 and +20 km/s clouds and the CND, the very high H$_2$O abundances aresuggested to be caused by the combined action of shock desorption from icygrain mantles and high-temperature, gas-phase shock chemistry. Only three ofthe molecules are briefly discussed here. For OH and H$_2$O three of the nineobserved positions are shown, while a map of the C$^{18}$O emission isprovided. An extensive paper was recently published with Open Access (Karlssonet al. 2013; http://www.aanda.org/articles/aa/pdf/2013/06/aa20471-12.pdf ).

Hydroxyl, water, ammonia, carbon monoxide and neutral carbon towards the Sgr A complex