The FTIR spectrum for a heavily oxidized porous silicon (PS) surface is considered. It is suggested that a portion of this spectrum be reassigned to the Si=O stretch frequency of a surface bound-silanone-based silicon oxyhydride consistent also with the O-18(2)/O-16(2) isotopic labeling of the FTIR spectrum and with matrix isolation infrared spectra for silanone, silanoic acid, and silicic acid. Within the framework of this assignment the FTIR spectrum, the photoluminescence excitation spectrum, and the visible photoluminescence spectrum of PS correlate well with a surface-bound silanone-based silicon oxyhydride fluorophor.