The majority of the LIRGs show evidence of interaction with other galaxies or having recently experienced a galaxy merger, and the same holds true for the LIRGs that host hydroxyl megamasers. Megamaser hosts are rich in molecular gas compared to spiral galaxies, with molecular hydrogen masses in excess of one billion solar masses, or H2 > . Mergers help funnel molecular gas to the nuclear region of the LIRG, producing high molecular densities and stimulating high star formation rates characteristic of LIRGs. The starlight in turn heats dust, which re-radiates in the far infrared and produces the high LFIR observed in hydroxyl megamaser hosts. The dust temperatures derived from far infrared fluxes are warm relative to spirals, ranging from 40–90 K.