Disclosed is a perfluoropolyether (PFPE) lubricant comprising less than about 10 percent PFPE molecules having a molecular weight lower than about 2000 Daltons, and wherein the average molecular weight of the lubricant is greater than about 5000 Daltons. Such a lubricant comprises less than about 15 percent PFPE molecules having a moleuclar weight greater than about 10,000 Daltons. Also disclosed is a thin film magnetic disc comprising a recording surface and a PFPE lubricant in contact with the recording surface. The recording surface of such a thin film magnetic disc can be adapted to magnetically record information via an air bearing read/write head. The recording surface can be smooth. The disc can further comprise a rough-surfaced landing zone inward of the recording surface, wherein the PFPE lubricant is in contact with the landing zone. Also disclosed is a method of lubricating a thin film magnetic disc. The method can comprise applying a narrow, high molecular weight fractionated PFPE lubricant to the disc. In addition, a method of preparing a PFPE lubricant for use with a thin film magnetic disc is disclosed. The method can comprise fractionating a PFPE lubricant to include less than about 10 percent PFPE molecules having a molecular weight lower than about 2000 Daltons. The average molecular weight of such a lubricant after fractionation is greater than about 5000 Daltons.