Antimony-121 Mössbauer Spectral Study of the Eu₁₄MnSb₁₁ and Yb₁₄MnSb₁₁ Zintl Compounds

Abstract

The antimony-121 Mössbauer spectra of the Yb14MnSb11 and Eu14MnSb11 Zintl compounds have been measured between 2 or 5 and 300 K. The resulting three-dimensional arrays of the spectral counts, velocity, and temperature have been simultaneously fit with a minimum number of free parameters. These fits yield a 0 Kelvin transferred hyperfine field of 2.9(2) T, a Curie temperature of 57(3) K, and a Mössbauer temperature of 182(2) K for Yb14MnSb11; in this case the transferred field arises solely from the ordering of Mn2+. Because Eu14MnSb11 has both Eu2+ and Mn2+ ions that are magnetically ordered, its antimony-121 Mössbauer spectra are more complex and reveal two magnetic transitions, the first at 92(1) K resulting from the ordering of the Mn2+ ions and the second at 9.5(1.0) K resulting from the ordering of the Eu2+ ions; the corresponding 0 Kelvin transferred hyperfine fields are 1.3(1) and 3.7(1) T. The antimony-121 isomer shifts yield electronic configurations of 5s1.745p4.28 and 5s1.745p4.19 for the average antimony anion in Yb14MnSb11 and Eu14MnSb11, respectively.

Eu9Cd4–xCM2+x–y□ySb9: Ca9Mn4Bi9-Type Structure Stuffed with Coinage Metals (Cu, Ag, and Au) and the Challenges with Classical Valence Theory in Describing These Possible Zintl Phases

“…Note that the observation of a hyperfine field for Eu 3+ requires significant mixing of the diamagnetic J = 0 ground state with the J = 1 first excited state. Transferred hyperfine fields at Eu 3+ were also observed in iron garnet and Eu 3 S 4 as well as in the Zintl phase Eu 14 MnP 11 , which supports the assignment of a Eu 3+ hyperfine field in the samples discussed herein. Reported Eu 3+ -transferred fields at low temperatures range from about 5 T in Eu 3 S 4 below 3.2 K and 33 T in Eu 14 MnP 11 at 4.2 K .…”

“…Transferred hyperfine fields at Eu 3+ were also observed in iron garnet and Eu 3 S 4 as well as in the Zintl phase Eu 14 MnP 11 , which supports the assignment of a Eu 3+ hyperfine field in the samples discussed herein. Reported Eu 3+ -transferred fields at low temperatures range from about 5 T in Eu 3 S 4 below 3.2 K and 33 T in Eu 14 MnP 11 at 4.2 K . Considering the distances between magnetic moments, which are 3.99 Å in the former and 3.58–3.82 Å in the latter compound, a correlation between the Eu 2+ –Eu 3+ distance and transferred field is likely.…”

“…Although contributing much less in the Ag-containing sample, Eu 3+ has to be taken into account in order to achieve satisfactory fits at both temperatures. However, in this case, it was necessary to fix the line width of the Eu 3+ component at 50 K. Considering the five different crystallographic Eu sites in these compounds, the pronounced line widths obtained are not surprising and are comparable to results obtained for other Zintl compounds with multiple Eu sites …”

Multi-temperature Synchrotron Powder X-ray Diffraction Study and Hirshfeld Surface Analysis of Chemical Bonding in the Thermoelectric Zintl Phase Yb14MnSb11

“…In addition to this complex structure and the large unit cell, the many possibilities of tuning the thermoelectric properties through chemical doping or alloying make the 14-1-11 phases attractive for thermoelectric applications. The general formula of the family of Ca 14 AlSb 11 compounds is A 14 MPn 11 , where A is an alkaline earth or divalent rare-earth element (Ca, Sr, Ba, Yb, Eu), M is a transition metal or a group 13 element (Mn, Zn, Al, Ga, In), and Pn is a group 15 element (P, As, Sb, Bi). − ,− While 14-1-11 phases containing a group 13 element (as Ca 14 AlSb 11 with Al 3+ ) are diamagnetic semiconductors, the Yb 14 MnSb 11 structure containing Mn 2+ is a ferromagnetic p-type metal. Substitutions of the three components affect the magnetic and transport properties by altering the number of charge carriers.…”

Best Practices and Protocols in Mössbauer Spectroscopy

“…Because Mössbauer spectroscopy is mainly used in the study of iron containing compounds, this paper will be limited to iron-57 Mössbauer spectroscopy and to the most often used transmission iron-57 Mössbauer spectroscopy. However, other Mössbauer nuclei, for instance, tin-119, − antimony-121, , and europium-151, , are often used for the characterization of solid compounds. Because both iron-57 and tin-119 have a nuclear ground state spin of I g = 1/2 and a nuclear excited state spin of I e = 3/2, most of the results discussed below for iron-57 may be transferred to tin-119 spectra with a simple change in the parameters of the tin-119 Mössbauer nuclide.…”