Crystal Field Analysis of the Magnetization Curves of HoFe11Ti under High Pressure

2013 ◽  
Vol 818 ◽  
pp. 72-76 ◽  
Author(s):  
Gang Su

The crystalline electric field parameters Anmfor HoFe11Ti under different pressures were evaluated by fitting calculations to the magnetization curves measured on the single crystals at several temperatures. It was found that magneto-crystalline anisotropy has been changed by high pressure and the Anmfor HoFe11Ti under high pressures are strikingly different from Anmfor the corresponding HoFe11Ti H with interstitial hydrogen atom.

1996 ◽  
Vol 53 (10) ◽  
pp. 6829-6835 ◽  
Author(s):  
S. Uma ◽  
T. Sarkar ◽  
K. Sethupathi ◽  
M. Seshasayee ◽  
G. Rangarajan ◽  
...  

1953 ◽  
Vol 31 (5) ◽  
pp. 820-836 ◽  
Author(s):  
G. M. Volkoff

The dependence of electric quadrupole splitting of nuclear magnetic resonance absorption lines in single crystals on crystal orientation in an external magnetic field is investigated theoretically following earlier work of Pound, of Volkoff, Petch, and Smellie, and of Bersohn. Explicit formulae are given, applicable to non axially symmetric crystalline electric field gradients (η ≠ 0), and valid up to terms of the second order in the quadrupole coupling constant [Formula: see text], for the dependence of the absorption frequencies on the angle of rotation of the crystal about any arbitrary axis perpendicular to the magnetic field. Some formulae including third order effects in Cz are also given. It is shown that an experimental study of the dependence of this splitting on the angles of rotation about any two arbitrary mutually perpendicular axes is sufficient, when second order effects are measurable, to yield the values of | Cz |, η, and the orientation of the principal axes of the electric field gradient tensor at the nuclear sites. In the case that the direction of one of the principal axes is known from crystal symmetry, a single rotation about this axis gives the complete information.A new method of determining nuclear spin I is proposed which depends on comparing first and second order shifts of the resonance frequencies of the strong inner line components. The method will be of interest in those cases where the total number 2I of line components can not be unambiguously ascertained owing to the outer line components being excessively broadened and weakened by crystal imperfections.


1996 ◽  
Vol 223-224 ◽  
pp. 565-567 ◽  
Author(s):  
Narayani Senthilkumaran ◽  
T Sarkar ◽  
G Rangarajan ◽  
Chen Changkang ◽  
J.W Hodby ◽  
...  

2002 ◽  
Vol 123 (8) ◽  
pp. 327-331 ◽  
Author(s):  
V Tsurkan ◽  
M Mücksch ◽  
H.-A Krug von Nidda ◽  
J Hemberger ◽  
D Samusi ◽  
...  

2002 ◽  
Vol 57 (12) ◽  
pp. 915-918 ◽  
Author(s):  
Y. P. Varshni

The effect of high pressure on a hydrogen atom has frequently been simulated by enclosing the atom in an impenetrable spherical box. It is shown that for such a confined hydrogen atom placed at the centre of a spherical box a simple scaling relation exists between the energy and the radius of the confining box for 1s, 2p, 3d, and 4f levels, and another similar relation exists for 2s, 3p, and 4d levels.


2010 ◽  
Vol 25 (2) ◽  
pp. 396-400 ◽  
Author(s):  
Andrew K. Stemshorn ◽  
Georgiy Tsoi ◽  
Yogesh K. Vohra ◽  
Stanislav Sinogeiken ◽  
Phillip M. Wu ◽  
...  

In this study, we report low temperature x-ray diffraction studies combined with electrical resistance measurements on single crystals of iron-based layered superconductor FeSe to a temperature of 10 K and a pressure of 44 GPa. The low temperature high pressure x-ray diffraction studies were performed using a synchrotron source and superconductivity at high pressure was studied using designer diamond anvils. At ambient temperature, the FeSe sample shows a phase transformation from a PbO-type tetragonal phase to a NiAs-type hexagonal phase at 10 ± 2 GPa. On cooling, a structural distortion from a PbO-type tetragonal phase to an orthorhombic Cmma phase is observed below 100 K. At a low temperature of 10 K, compression of the orthorhombic Cmma phase results in a gradual transformation to an amorphous phase above 15 GPa. The transformation to the amorphous phase is completed by 40 GPa at 10 K. A loss of superconductivity is observed in the amorphous phase and a dramatic change in the temperature behavior of electrical resistance indicates formation of a semiconducting state at high pressures and low temperatures. The formation of the amorphous phase is attributed to a kinetic hindrance to the growth of a hexagonal NiAs phase under high pressures and low temperatures.


2006 ◽  
Vol 301 (2) ◽  
pp. 398-406 ◽  
Author(s):  
M. Frontzek ◽  
A. Kreyssig ◽  
M. Doerr ◽  
M. Rotter ◽  
G. Behr ◽  
...  

1990 ◽  
Vol 45 (2) ◽  
pp. 107-110 ◽  
Author(s):  
Klaus-Jürgen Range ◽  
Wilhelm Hegenbart ◽  
Anton M. Heyns ◽  
Franz Rau ◽  
Ulrich Klement

Potassium tungstate, K2WO4, decomposes at high pressures to give K2W2O7 and other products. Single crystals of K2W2O7 could be synthesized from a mixture of K2WO4 + WO3 at 40kbar, 1000 °C. The crystals are monoclinic, space group P21/c, with a = 3.883(1) A, b = 13.653(4) Å, c = 5.960(1) Å, β = 90.40(3)°, and Ζ = 2.The structure is comprise of distorted WO6-octahedra (W–O = 1.75-2.13 A) which are connected by corner- and edgesharing, thus forming layers with a sequence ABAB ... along [010]. The potassium ions are situated between the layers with K–O distances of 2.66-3.04 A.Rb2W2O7, synthesized from a Rb2WO4/WO3-mixture at 40 kbar, 1000 °C, is isostructural with K2W2O7 (a = 3.9645(4) Å, b = 14.119(1) Å, c = 6.0415(5) Å,β = 90.446(9)°.


Sign in / Sign up

Export Citation Format

Share Document