Chemical evolution in the LMC with a new model

We varied the hydrogen number density between 1x10^5^ and 5x10^5^/cm3 and, for each density, we ran models for A_V_=3, 5, and 10. Then, for each density and visual extinction we varied the grain temperature between 10 and 50K in small intervals, while keeping the gas temperature constant at 20K.

We used a gas-to-dust mass ratio based on a variety of observations and analyses, and scaled the elemental abundances of the LMC so that they are representative of so-called "low" metallic abundances. We found that although the LMC is metal-poor, it still shows a rich chemistry; almost all the major observed species in the gas phase of our Galaxy should be detectable using present-day observational facilities. We compared our model results with observed gas-phase abundances in some cold and dense sources, and found reasonably good agreement for most species.