An infrared signal thought to reveal how molecules in perovskite solar materials respond to light-generated charges can arise largely from the way light travels through the thin film itself, a new theoretical study shows. Jun Nishida, assistant professor at the Institute for Molecular Science (IMS), Japan, found that light-generated charges alter how infrared light is reflected and transmitted within the film layers, producing sharp features that resemble changes in molecular vibrations even when the vibrations themselves are unaltered. ...read more read less