Rohrmann Urban, Schwerdtfeger Peter, Schäfer Rolf
Eduard-Zintl-Institut, Technische Universität Darmstadt, Darmstadt, Germany.
Phys Chem Chem Phys. 2014 Nov 21;16(43):23952-66. doi: 10.1039/c4cp02994a. Epub 2014 Oct 6.
We present extensive temperature dependent (16-70 K) magnetic and electric molecular beam deflection measurements on neutral manganese doped tin clusters Mn/SnN (N = 9-18). Cluster geometries are identified by comparison of electric deflection profiles and quantum chemical data obtained from DFT calculations. Most clusters adopt endohedral cage structures and all clusters exhibit non-vanishing magnetic dipole moments. In the high temperature regime all species show exclusively high field seeking magnetic response and the magnetic dipole moments are extracted from the shift of the molecular beam. At low nozzle temperatures, some of the clusters show considerably broadened beam profiles due to non-uniform deflection in the magnetic field. The results reflect the influence of the chemical environment on the magnetic properties of the transition metal in atomic domain magnetic nanoalloys. Different ground state spin multiplicities and coupling of rotational and vibrational degrees of freedom with the spin angular momentum of isolated clusters of different size apparently cause these variations of spin orientation. This is discussed by taking electronic and molecular structure data into account.
我们展示了对中性锰掺杂锡团簇Mn/SnN(N = 9 - 18)进行的广泛的温度相关(16 - 70 K)磁和电分子束偏转测量。通过比较电偏转轮廓和从密度泛函理论(DFT)计算获得的量子化学数据来确定团簇几何结构。大多数团簇采用内包笼状结构,并且所有团簇都表现出非零的磁偶极矩。在高温 regime 下,所有物种仅表现出高场寻磁响应,并且磁偶极矩是从分子束的偏移中提取的。在低喷嘴温度下,由于磁场中的不均匀偏转,一些团簇显示出明显变宽的束轮廓。结果反映了化学环境对原子域磁性纳米合金中过渡金属磁性能的影响。不同的基态自旋多重性以及不同大小的孤立团簇的转动和振动自由度与自旋角动量的耦合显然导致了这些自旋取向的变化。通过考虑电子和分子结构数据对此进行了讨论。