Computer-Modeling Study of the Interactions of Zdol with Amorphous Carbon Surfaces

Abstract

The formation of a tribologically reliable interface between the magnetic recording disk and the magnetic recording head in hard-disk drives is predicated upon the presence of a molecularly thin perfluoropolyether (PFPE) lubricant film. The molecular interactions that develop between the PFPE lubricant and the underlying amorphous carbon overcoat of the magnetic recording disk govern the adhesion, physical coverage, thermal stability, and mobility of the lubricant on the carbon surface and hence are of paramount importance in defining the tribological performance of the drive. In this work, information pertaining to the interfacial interactions between the hydroxyl-terminated PFPE lubricant Zdol and amorphous carbon surfaces is obtained via ab initio calculations. The small fluorinated ether molecules CF3OCF2CH2OH (ZD) and CF3OCF3 (PFDME) were used as computationally tractable models for the PFPE lubricants. A population analysis is performed on the ZD model lubricant and the various chemical functionalit...