Giovannini Mauro, Čurlík Ivan, Freccero Riccardo, Solokha Pavlo, Reiffers Marian, Sereni Julian
Department of Chemistry, University of Genova, Via Dodecaneso 31, 16146 Genova, Italy.
Faculty of Humanities and Natural Sciences, University of Prešov, 17 Novembra 1, 080 01 Prešov, Slovakia.
Inorg Chem. 2021 Jun 7;60(11):8085-8092. doi: 10.1021/acs.inorgchem.1c00678. Epub 2021 May 24.
The new intermetallic compound EuPdSn has been investigated. A single crystal was selected from the alloy and was analyzed by single-crystal X-ray diffraction, revealing that this compound possesses the noncentrosymmetric CaPdGe structure type being, so far, the only rare-earth-based representative. Bonding analysis, performed on the basis of DOS and (I)COHP, reveals the presence of strong covalent Sn-Pd bonds in addition to linear and equidistant Pd-Pd chains. The incomplete ionization of Eu leads to its participation in weaker covalent interactions. The magnetic effective moment, extracted from the magnetic susceptibility is = 7.87 μ, close to the free ion Eu value ( = 7.94 μ). The maximum of at ∼ 13 K indicates an antiferromagnetic behavior below this temperature. A coincident sharp anomaly in the specific heat () emerges from a broad anomaly centered at around 10 K. From the reduced jump in the heat capacity at a scenario of a transition to an incommensurate antiferromagnetic phase below followed by a commensurate configuration below 10 K is suggested.
新型金属间化合物EuPdSn已被研究。从该合金中选取了一块单晶，并通过单晶X射线衍射进行分析，结果表明该化合物具有非中心对称的CaPdGe结构类型，是目前唯一的稀土基代表物。基于态密度（DOS）和（I）COHP进行的键合分析表明，除了线性且等距的Pd-Pd链外，还存在强共价Sn-Pd键。Eu的不完全电离导致其参与较弱的共价相互作用。从磁化率中提取的磁有效矩为μeff = 7.87 μB，接近自由离子Eu的值（μeff = 7.94 μB）。在T ∼ 13 K时χ的最大值表明在此温度以下存在反铁磁行为。比热（Cp）中一个重合的尖锐异常从以10 K左右为中心的宽异常中出现。根据在TN处热容量的减小跳跃，推测在TN以下转变为非公度反铁磁相，随后在10 K以下转变为共格构型。
