Molecular and Ionic shocks in the Supernova Remnant 3 C 391

New observations of the supernova remnant 3C 391 are presented in the nearinfrared, using the H2 2.12 μm and [Fe II] 1.64 μm narrow-band filters in the Prime Focus Infrared Camera on the Palomar Observatory Hale 200 telescope, and in the mid-infrared, using the circular-variable filters in the ISOCAM on the Infrared Space Observatory. Shocked H2 emission was detected from the region 3C 391:BML (40 size), where broad millimeter CO and CS lines had previously been detected. A small H2 clump, 45 ′′ from the main body of 3C 391:BML, was confirmed to have broad CO emission, demonstrating that the near-infrared H2 images can trace previously undetected molecular shocks. The [Fe II] emission has a significantly different distribution, being brightest in the bright radio bar, at the interface between the supernova remnant and the giant molecular cloud, and following filaments in the radio shell. The near-infrared [Fe II] and the midinfrared 12–18 μm filter (dominated by [Ne II] and [Ne III] images are the first images to reveal the radiative shell of 3C 391. The mid-infrared spectrum is dominated by bright ionic lines of [Fe II] 5.5 μm, [Ar II] 6.9 μm, [Ne II] 12.8 μm, and [Ne III] 15.5 μm, as well as the series of pure rotational lines of H2 S(2) through S(7). There are no aromatic hydrocarbons associated with the shocks, nor is their any mid-infrared continuum, suggesting that macromolecules and very small grains are destroyed in the shocks. Comparing 3C 391 to the betterstudied IC 443, both remnants have molecularand ionic-dominated regions; for 3C 391, the ionic-dominated region is the interface into the giant molecular cloud,