Atomistic simulation method in head-disk interface of magnetic data storage systems

The conventional modeling paradigm of head-disk interface (HDI) in magnetic data storage systems was based on meso/macro scale modeling. We investigate inter-molecular interaction energy for four sets of model PFPE dimers and elucidate the importance of hydrogen bonding between the hydroxylated functional endgroups in interaction strength. We found that for these model dimers representing PFPEs, the DDPA-DDPA (non-hydroxylated) dimer demonstrates the least stable interaction. We further investigated binary blends of hydroxylated and non-hydroxylated model PFPE lubricant and observed diminished interaction strength as compared to pure hydroxylated dimers. Our atomistic interaction energy study reported here will provide insight for tuning physiochemical properties of lubricant film by controlling blending ratios and chain end functionality to obtain desired lubricant performance.