Magnetic hyperfine structure of Tm2+ ions in TmTe

Rare Earth Mössbauer Spectroscopy Measurements on Lanthanide Intermetallics

“…At T ¼ 57 mK, H eff ¼ 345 T (the free ion value of Tm 2þ is 693 T) and QS ¼ 13.8 AE 0.2 cm/s (the free ion value of Tm 2þ is 16.86 cm/s). Triplett et al (1978) argue that the large value of QS at T ¼ 0.057 K is indicative of a non-cubic symmetry at the Tm site in TmTe. Moreover, as seen in Fig.…”

“…The result amounts to A 2 0 h r 2 i ¼ 110 K and A 2 0 h r 2 i ¼ 11 K, giving a total splitting of 124 K. The 169 Tm Mössbauer spectra of TmTe taken well below the magnetic ordering temperature T N (somewhere near 0.3 K for this sample) are shown in Fig. 4.21 (Triplett et al, 1978). The spectra consist of a six-line hyperfine pattern and a non-magnetic quadrupole doublet, which will be regarded as a contaminant in the basic magnetic spectrum.…”

“…Uhrich and Barnes (1967) have determined the lowest crystal field parameter B 2 0 ¼0.53 K from electric quadrupole splitting measurements above T N ¼ 56 K. Cohen (1968) has interpreted the 169 Tm spectra of Tm metal with an incommensurate magnetic structure supposing a fast relaxation limit. In contrast, Dixon et al (1980) has interpreted these spectra of Tm metal by including electronic relaxation using the matrix formalism of Hirst et al (1969).…”

“…The spectra consist of a six-line hyperfine pattern and a non-magnetic quadrupole doublet, which will be regarded as a contaminant in the basic magnetic spectrum. The dominant character of the lowest level of the ground multiplet of Tm 2þ ( 2 F 7/2 ) is established by the observation that the only parameter which changes significantly when the temperature is lowered from T ¼ 0.127 to 0.057 K is the nuclear Triplett et al (1978). The solid lines through the data are fits composed of a magnetic six-line hyperfine pattern and a non-magnetic quadrupole doublet (dashed lines) which comprises about 23% of the total spectral weight.…”

“…4.22. The curve is a fit to the data and was generated from the thermally averaged quadrupole interaction Triplett et al, 1978).…”