Provided are infrared reflective films comprising a substrate and at least one infrared reflective layer comprising an aminium radical cation compound in a crystalline state and an organic polymer, wherein the infrared reflective layer has a reflectance peak in the infrared region from 1250 nm to 1700 nm. Such infrared films are stable in their optical properties against degradation by light and moisture. Also provided are solar control window films, security markings, and other optical articles comprising such infrared reflective films. Further provided are methods for making such infrared reflective films.