A fluorochemical ketone compound consists of two terminal, branched, independently fluoroalkylcarbonyl or perfluoroalkylcarbonyl groups and an intervening linear perfluoropolyether segment, each of the terminal groups optionally comprising at least one catenated heteroatom, and the perfluoropolyether segment consisting essentially of at least one tetrafluoroethyleneoxy moiety and, optionally, at least one difluoromethyleneoxy moiety, the moieties being randomly or non-randomly distributed within the perfluoropolyether segment.