Crystal field interaction at the Tm3+ site in TmCr2Si2

TmCr2Si2 is investigated using 169Tm-Mössbauer spectroscopy and specific heat measurements. The Tm sub-lattice is not magnetically ordered down to 2 K, in keeping with the observed singlet crystal field ground state. The fitted crystal field parameters are consistent with those determined elsewhere for isostructural HoCr2Si2 and indicate a deviation of the rank 6 parameters from the trend observed so far for the series RT2Si2 (R = rare earth, T = Fe, Co, Ni, Cu).