Evidence for low-temperature isotopic ordering in methyl-monodeuterated lithium acetate dihydrate

We measured the heat capacities of methyl-monodeuterated lithium acetate dihydrate single crystals (LiC2H2DO2·2H2O) at 2K

► Cp measurements of mono-methyl-deuterated LiC2H2DO2·2H2O show transition at 5.5 K.
► Transition is in addition to the 14 K ordering transition.
► Transition is suggested to be due to isotopic ordering.