Phase transitions of Ising mixed spin 1 and 3/2 with random crystal field distribution

2016 ◽  
Vol 460 ◽  
pp. 210-221 ◽  
Author(s):  
S. Sabri ◽  
M. EL Falaki ◽  
M. EL Yadari ◽  
A. Benyoussef ◽  
A. EL Kenz
Keyword(s):  
Phase Transitions ◽  
Crystal Field ◽  
Field Distribution ◽  
Mixed Spin

Magnetic properties of the mixed spin-5/2 and spin-3/2 Blume-Capel Ising system on the two-fold Cayley tree

Open Physics ◽  
2009 ◽  
Vol 7 (3) ◽  
Author(s):  
Rachidi Yessoufou ◽  
Saliou Amoussa ◽  
Felix Hontinfinde
Keyword(s):  
Magnetic Properties ◽  
Phase Transitions ◽  
Crystal Field ◽  
Cayley Tree ◽  
Second Order ◽  
Coordination Numbers ◽  
First Order ◽  
Mixed Spin ◽  
Second Order Transition ◽  
Zero Values

AbstractWe use exact recursion relations to study the magnetic properties of the half-integer mixed spin-5/2 and spin-3/2 Blume-Capel Ising ferromagnetic system on the two-fold Cayley tree that consists of two sublattices A and B. Two positive crystal-field interactions Δ1 and Δ2 are considered for the sublattice with spin-5/2 and spin-3/2 respectively. For different coordination numbers q of the Cayley tree sites, the phase diagrams of the model are presented with a special emphasis on the case q = 3, since other values of q reproduce similar results. First, the T = 0 phase diagram is illustrated in the (D A = Δ1/J,D B = Δ2/J) plane of reduced crystal-field interactions. This diagram shows triple points and coexistence lines between thermodynamically stable phases. Secondly, the thermal variation of the magnetization belonging to each sublattice for some coordination numbers q are investigated as well as the Helmoltz free energy of the system. First-order and second-order phase transitions are found. The second-order phase transitions become sharper and sharper when D A or D B increases. The first-order transitions only exist for some appropriate non-zero values of D A and/or D B. The corresponding transition lines never connect to the second-order transition lines. Thus, the non-existence of tricritical points remains one of the key features of the present model. The magnetic exponent β 0 of the model is estimated and found to be ¼ at small values of D A = D B = D and β 0 = ½ at large values of D. At intermediate values of D, there is a crossover region where the magnetic exponent displays interesting behaviours.

ChemInform Abstract: Phase Transitions and Crystal-Field Levels in Nd2NiO4.

ChemInform ◽  
2010 ◽  
Vol 27 (14) ◽  
pp. no-no
Author(s):  
M. CASTRO ◽  
R. BURRIEL
Keyword(s):  
Phase Transitions ◽  
Crystal Field

Random Crystal Field in a Mixed Spin S =  1/2 and S =  3/2 Ising Model by Renormalization Group Theory

2018 ◽  
Vol 31 (12) ◽  
pp. 3949-3957 ◽  
Author(s):  
S. Zouhair ◽  
M. Monkade ◽  
M. Bourass ◽  
A. El Antari ◽  
M. El Bouziani ◽  
...  
Keyword(s):  
Renormalization Group ◽  
Group Theory ◽  
Ising Model ◽  
Crystal Field ◽  
Renormalization Group Theory ◽  
Mixed Spin

Triple mixed-spin Ising model

2020 ◽  
Vol 34 (13) ◽  
pp. 2050129
Author(s):  
Erhan Albayrak
Keyword(s):  
Phase Transitions ◽  
Ising Model ◽  
Magnetic Fields ◽  
Exchange Interaction ◽  
Spin System ◽  
Bethe Lattice ◽  
Nearest Neighbors ◽  
Recursion Relations ◽  
Mixed Spin ◽  
Exchange Interaction Parameter

The A, B and C atoms with spin-1/2, spin-3/2 and spin-5/2 are joined together sequentially on the Bethe lattice in the form of ABCABC[Formula: see text] to simulate a molecule as a triple mixed-spin system. The spins are assumed to be interacting with only their nearest-neighbors via bilinear exchange interaction parameter in addition to crystal and external magnetic fields. The order-parameters are obtained in terms of exact recursion relations, then from the study of their thermal variations, the phase diagrams are calculated on the possible planes of our system. It is found that the model gives only second-order phase transitions in addition to the compensation temperatures.

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