An infrared transmissive article includes an infrared transmissive substrate and a single layer anti-reflective (AR) composite broadband sol gel coating on a surface of the substrate. The AR coating includes a first chalcogenide including compound, and a second chalcogenide including compound intermixed with the first chalcogenide including compound. The percentages of the first chalcogenide and the second chalcogenide in the AR coating are selected to provide a refractive index of the AR coating that approximates the square root of a refractive index of the substrate.