Antiferromagnetic order in the Heusler alloy, Ni2Mn(MnxSn1−x)

1978 ◽  
Vol 56 (6) ◽  
pp. 674-677 ◽  
Author(s):  
C. V. Stager ◽  
C. C. M. Campbell

A series of Heusler alloys, with composition Ni2Mn(MnxSn1−x) has been studied. X-Ray and neutron diffraction techniques have been used to investigate the chemical order. Well-ordered alloys were prepared with compositions corresponding to x = 0.1. 0.2, 0.3, and 0.4. The magnetic properties of these ordered alloys indicate that the Mn atoms, which substitute for Sn atoms, are coupled antiferromagnetically to the ferromagnetic manganese sublattice.

2002 ◽  
Vol 718 ◽  
Author(s):  
Job Rijssenbeek ◽  
Sylvie Malo ◽  
Takashi Saito ◽  
Vincent Caignaert ◽  
Masaki Azuma ◽  
...  

AbstractPerovskite-like mixed metal ruthenates are of interest owing to their varied electronic and magnetic properties, which are heavily dependent on the ordering of the transition metals. We report the synthesis and structural characterization of the first 1:2 ordered perovskite ruthenate, Sr3CaRu2O9. The structure was determined from a combination of powder X-ray, electron and neutron diffraction data and is characterized by a 1:2 ordering of Ca2+ and Ru5+ over the sixcoordinate B-sites of the perovskite lattice. Sr3CaRu2O9 is the first example of this structure-type to include a majority metal with d electrons (Ru(V), d3). The relationship of this material to the K2NiF4-type Sr1.5Ca0.5RuO4 (i.e., Sr3CaRu2O8) highlights the dramatic effects of the ruthenium valence on the resultant structure. Remarkably, these two structures can be quantitatively interconverted by the appropriate choice of reaction temperature and atmosphere.


RSC Advances ◽  
2019 ◽  
Vol 9 (63) ◽  
pp. 36680-36689
Author(s):  
M. Ram ◽  
A. Saxena ◽  
Abeer E. Aly ◽  
A. Shankar

The electronic and magnetic properties of Mn2ZnSi(1−x)Gex (x = 0.0, 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875, and 1.0) inverse Heusler alloys and Mn2ZnSi/Mn2ZnGe superlattice have been investigated using first-principles calculations.


2017 ◽  
pp. 31-36
Author(s):  
Prakash Sharma ◽  
Gopi Chandra Kaphle

Heusler alloys have been of great interest because of their application in the field of modern technological word. Electronic and magnetic properties of Co, Mn, Si and the Heusler alloy Co2MnSi have been studied using Density functional theory based Tight Binding Linear Muffin Tin Orbital with Atomic Sphere Approximation (TB-LMTO-ASA) approach. From the calculation lattice parameter of optimized structure of Co, Mn, Si and Co2MnSi are found to be 2.52A0 , 3.49A0 , 5.50A0 , 5.53A0 respectively. Band structure calculations show that Co and Mn are metallic, Si as semi-conducting while the Heusler alloy Co2MnSi as half-metallic in nature with band gap 0.29eV. The charge density plot indicates major bonds in Co2MnSi are ionic in nature. Magnetic property has been studied using the density of states (DOS), indicating that Co and Co2MnSi are magnetic with magnetic moment 2.85μB and 4.91μB respectively. The contribution of orbitals in band, DOS and magnetic moment are due to d-orbitals of Co and Mn and little from s and p-orbital of Si in Co2MnSi.The Himalayan Physics Vol. 6 & 7, April 2017 (31-36)


Author(s):  
F. Frey ◽  
E. Weidner

AbstractComplementary neutron and x-ray diffuse scattering may provide insight into structural super-ordering and disordering of decagonal quasicrystals (d-phases), and, in consequence, into the formation and stability of aperiodically ordered alloys. Neutron diffraction makes a contrasting almost isoelectronic atomic species possible, as well as a separation of elastic and inelastic diffuse intensity contributions. Experimental work at high temperatures is comparatively unproblematic. The method suffers, however, from the difficulty in obtaining sufficiently sized mono-grain samples and a lack of dedicated neutron diffraction instruments. Recent results, with a main focus on high-temperature (<1000°C) investigations of disordered decagonal Al—Ni—Co phases are reported and some tentative models are discussed.


2012 ◽  
Vol 189 ◽  
pp. 189-208 ◽  
Author(s):  
Vijay Srivastava ◽  
Kanwal Preet Bhatti

Although Heusler alloys have been known for more than a century, but since the last decade there has been a quantum jump in research in this area. Heusler alloys show remarkable properties, such as ferromagnetic shape memory effect, magnetocaloric effect, half metallicity, and most recently it has been shown that it can be used for direct conversion of heat into electricity. Heusler alloys Ni-Mn-Z (Z=Ga, Al, In, Sn, Sb), show a reversible martensitic transformation and unusual magnetic properties. Other classes of intermetallic Heusler alloy families that are half metallic (such as the half Heusler alloys Ni-Mn-Sb and the full Heusler alloy Co2MnGe) are attractive because of their high Curie temperature and structural similarity to binary semiconductors. Unlike Ni-Mn-Ga, Ni-Mn-In and Ni-Mn-Sn transform from ferromagnetic austenite to non-ferromagnetic martensite. As is consistent with the Clausius-Clapeyron equation, the martensitic phase transformation can be manipulated by a magnetic field, leading to possible applications of these materials enabling the magnetic shape memory effect, energy conversion and solid state refrigeration. In this paper, we summarize the salient features of Heusler alloys, like the structure, magnetic properties and potential application of this family of alloys in industry.


Author(s):  
Fatiha Djaidi ◽  
Hanane Mechri ◽  
Mohammed Azzaz

Abstract The Fe2CrSi nanostructured Heusler alloy was prepared by mechanical alloying followed by heat treatment. The structure, microstructure, and magnetic properties of the samples were studied by the following analysis methods: X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectrometry, transmission electron microscopy, and a vibrating sample magnetometer. The a-Fe (Si, Cr) solid solution with a disordered body centered cubic (bcc) crystal structure was obtained after 24 h of milling. An example of the sample milled for 32 h with a disordered crystal structure a-Fe(Si, Cr) was chosen to investigate the transformation with temperature using differential scanning calorimetry. The effect of annealing temperatures on the structural, microstructural, and magnetic properties of the ordered Fe2CrSi Heusler phase for the sample milled for 32 h was investigated.


2011 ◽  
Vol 1327 ◽  
Author(s):  
Thomas F. Creel ◽  
Jinbo B. Yang ◽  
Mehmet Kahveci ◽  
Jagat Lamsal ◽  
Satish K. Malik ◽  
...  

ABSTRACTWe have studied the structural and magnetic properties of La0.7Sr0.3Mn1-xNixO3 (x=0.05, 0.10, 0.20, 0.30, and 0.40) perovskites using x-ray and neutron diffraction and magnetic measurements. To our knowledge, there exists no neutron diffraction data available for this group of perovskite compositions. Neutron (λ = 1.479Å) and x-ray (λ = 1.5481Å; Cu Kα) powder diffraction indicate that for x ≥ 0.1 all samples are two-phase with a rhombohedral perovskite structure (space group R-3c) and a small amount of NiO (space group Fm3m). Neutron diffraction data for the perovskite phase at 12K and 300K show ferromagnetic ordering for x ≤ 0.2 and antiferromagnetic ordering for x = 0.4. However, for x = 0.3, neutron diffraction data at 12K show coexisting ferromagnetic and antiferromagnetic ordering while at 300K no magnetic ordering is found. Magnetic measurements indicate that the Curie temperature decreases with increasing Ni content. The NiO phase for all samples was found to have antiferromagnetic ordering at 12K and 300K. The magnetic measurements are consistent with the neutron diffraction data and together indicate long-range magnetic ordering for samples at low temperature and transitions from ferromagnetic to paramagnetic to antiferromagnetic ordering for samples at room temperature.


2010 ◽  
Vol 168-169 ◽  
pp. 341-344 ◽  
Author(s):  
Nina Mironova-Ulmane ◽  
A. Kuzmin ◽  
J. Grabis ◽  
I. Sildos ◽  
V.I. Voronin ◽  
...  

Structure and magnetic properties of nickel oxide (NiO) nanopowders have been studied by X-ray/neutron diffraction, SQUID magnetometer, and micro-Raman spectroscopy. Our diffraction data indicate that at room temperature all NiO powders are antiferromagnetically ordered and have a rhombohedral (R-3m) phase. The SQUID magnetometry and Raman spectroscopy measurements support the presence of the antiferromagnetic ordering.


1996 ◽  
Vol 49 (5) ◽  
pp. 633 ◽  
Author(s):  
BN Figgis ◽  
PA Reynolds ◽  
FK Larsen ◽  
GA Williams ◽  
CD Delfs

The crystal structure of [As(C6H5)4] [TcNCl4] was determined at 120 K by X-ray diffraction and at 28 K by neutron diffraction. The crystals are tetragonal, space group P4/n, with a 1260.4(3) and c 773.2(2) pm at 120 K. The [TcNCl4]-anion possesses exact C4v symmetry, with Tc≡N distances of 160.3(2) and 162.5(4)pm at 120 and 28 K respectively. Magnetic susceptibilities were measured on single crystals from 300 to 4.5 K. The results indicate a well behaved S ½ system following the Curie-Weiss law with θ -0.13 K


Sign in / Sign up

Export Citation Format

Share Document