Magnetic Properties of a Binary Mixture of Paramagnetic Metallomesogens

1997 ◽  
Vol 488 ◽  
Author(s):  
Y. Shimizu ◽  
S. Tantrawong ◽  
M. Yoshida ◽  
T. Sugino
Keyword(s):  
Phase Transition ◽  
Phase Diagram ◽  
Magnetic Properties ◽  
Phase Transitions ◽  
Binary Mixture ◽  
Binary Phase Diagram ◽  
Full Range ◽  
Antiferromagnetic Interaction ◽  
Ferromagnetic Behavior ◽  
Pure Compounds

AbstractMagnetic properties of a binary mixture of mesogenic tetraphenylporphyrin Cu(II) and VO(IV) complexes are reported. These mesogens show two lamellar mesophases (DL and DLC) and a binary phase diagram revealed that each mesophase is miscible. The magnetic properties were investigated by magnetization measurements using SQUID. It was found that the magnetization of 1:1 mixture (mole% base) was larger than those of the pure compounds below ca. 190 K, whilst 1:3 and 3:1 mixtures showed the decrease of magnetization in the full range of temperature in which the measurements were carried out. It was shown that χ−1 vs. T plots did not obey Curie-Weiss law. For the VO(IV) complex and 1:1 mixture, stepwise changes could be recognized at the temperatures corresponding to the phase transitions. 1:1 mixture as well as Cu(II) and VO(IV) complexes totally involve antiferromagnetic interaction. However, ferromagnetic behavior in χ−1 vs. T plots was seen about DL - DLC phase transition.

scholarly journals Electric properties of olive oil under pressure

2021 ◽  
Author(s):  
L. T. Pawlicki ◽  
R. M. Siegoczyński ◽  
S. Ptasznik ◽  
K. Marszałek
Keyword(s):  
Molecular Structure ◽  
Phase Transition ◽  
Phase Diagram ◽  
Phase Transitions ◽  
Olive Oil ◽  
Material Parameters ◽  
First Order ◽  
Long Time ◽  
Capacitive Reactance ◽  
First Order Phase

AbstractThe main purpose of the experiment was a thermodynamic research with use of the electric methods chosen. The substance examined was olive oil. The paper presents the resistance, capacitive reactance, relative permittivity and resistivity of olive. Compression was applied with two mean velocities up to 450 MPa. The results were shown as functions of pressure and time and depicted on the impedance phase diagram. The three first order phase transitions have been detected. All the changes in material parameters were observed during phase transitions. The material parameters measured turned out to be the much more sensitive long-time phase transition factors than temperature. The values of material parameters and their dependence on pressure and time were compared with the molecular structure, arrangement of molecules and interactions between them. Knowledge about olive oil parameters change with pressure and its phase transitions is very important for olive oil production and conservation.

scholarly journals SUPERCONDUCTING PHASE TRANSITION IN THE NAMBU–JONA-LASINIO MODEL

2001 ◽  
Vol 16 (17) ◽  
pp. 1129-1138 ◽  
Author(s):  
M. SADZIKOWSKI
Keyword(s):  
Phase Transition ◽  
Phase Diagram ◽  
Phase Transitions ◽  
Superconducting Phase ◽  
Coupling Constants ◽  
Coupling Constant ◽  
Rich Phase ◽  
Quark Interaction ◽  
Quark Coupling ◽  
Superconducting Phase Transition

The Nambu–Bogoliubov–de Gennes method is applied to the problem of superconducting QCD. The effective quark–quark interaction is described within the framework of the Nambu–Jona-Lasinio model. The details of the phase diagram are given as a function of the strength of the quark–quark coupling constant G′. It is found that there is no superconducting phase transition when one uses the relation between the coupling constants G′ and G of the Nambu–Jona-Lasinio model which follows from the Fierz transformation. However, for other values of G′ one can find a rich phase structure containing both the chiral and the superconducting phase transitions.

QUANTUM PHASE TRANSITIONS AND ENTANGLEMENT IN J1–J2 MODEL

2004 ◽  
Vol 15 (08) ◽  
pp. 1095-1103 ◽  
Author(s):  
RECEP ERYIĞIT ◽  
RESUL ERYIĞIT ◽  
YIĞIT GÜNDÜÇ
Keyword(s):  
Phase Transition ◽  
Phase Diagram ◽  
Phase Transitions ◽  
Ground State ◽  
Abrupt Change ◽  
Quantum Phase Transitions ◽  
Nearest Neighbors ◽  
Competing Interactions ◽  
One Dimensional ◽  
Transition Points

We study ground state pairwise entanglement within one-dimensional spin-1/2 antiferromagnetic J1–J2 model with competing interactions. Contrary to some claims we found that frustration does not increase entanglement. Concurrence of nearest and next nearest neighbors are found to show abrupt change at phase transition points. We also show that the concurrence can be used to classify the phase diagram of the model in anisotropy–frustration plane.

THE GROUNDSTATES AND PHASES OF THE TWO-DIMENSIONAL FULLY FRUSTRATED XY MODEL

2009 ◽  
Vol 23 (20n21) ◽  
pp. 3939-3950
Author(s):  
PETTER MINNHAGEN ◽  
SEBASTIAN BERNHARDSSON ◽  
BEOM JUN KIM
Keyword(s):  
Phase Transition ◽  
Phase Diagram ◽  
Phase Transitions ◽  
Xy Model ◽  
Two Dimensional ◽  
Spin Configuration ◽  
Multicritical Points ◽  
Symmetry Phase

The 2D Fully Frustrated XY(FFXY) class of models is shown to contain a new groundstate in addition to the checkerboard groundstate of the standard 2D XY model. The spin configuration of this additional groundstate is obtained and its connection to a broken Z2-symmetry explained. This means that the class of 2D FFXY models belongs within a U(1) ⊗ Z2 ⊗ Z2-symmetry phase-transition representation. The phase diagram is reviewed and the central charges of the four multicritical points described. The implications for the standard 2D FFXY-model are discussed and elucidated, in particular with respect to the long standing controversy concerning the phase transitions of the standard 2D FFXY-model.

scholarly journals Фазовая диаграмма и особенности поведения мягких мод в твердых растворах со структурой хантита TbFe-=SUB=-3-x-=/SUB=-Ga-=SUB=-x-=/SUB=-(BO_3)-=SUB=-4-=/SUB=-

2022 ◽  
Vol 130 (1) ◽  
pp. 84
Author(s):  
А.С. Крылов ◽  
А.Н. Втюрин ◽  
И.А. Гудим ◽  
И.В. Немцев ◽  
С.Н. Крылова
Keyword(s):  
Phase Transition ◽  
Phase Diagram ◽  
Phase Transitions ◽  
Raman Spectra ◽  
Solid Solutions ◽  
Structural Phase ◽  
Temperature Phase ◽  
Structural Phase Transitions ◽  
Soft Modes ◽  
Temperature Phase Diagram

The Raman spectra of four crystals of TbFe3-хGax (BO3) 4 solid solutions (x from 0 to 0.54) were studied in the temperature range from 8 to 350 K. The temperatures of structural phase transitions were determined. The observed spectral behavior is characteristic to condensation and restoration of soft modes. Soft modes are associated with a structural phase transition from the R32 phase to the P3121 phase. The Compositions-Temperature phase diagram was constructed

Electric and Magnetic Properties of Transition-Metal Carbide Sc3TC4 (T=Co, Ru, Os)

2016 ◽  
Vol 257 ◽  
pp. 34-37
Author(s):  
Takuto Kazama ◽  
Minoru Maeda ◽  
Kouichi Takase ◽  
Yoshiki Takano ◽  
Tadataka Watanabe
Keyword(s):  
Phase Transition ◽  
Magnetic Properties ◽  
Phase Transitions ◽  
Transition Metal ◽  
Density Wave ◽  
Transition Metal Carbide ◽  
Superconducting Transition ◽  
Metal Carbides ◽  
Low Dimensional ◽  
Successive Phase

We investigate electric and magnetic properties of quasi-one-dimensional transition-metal carbides Sc3TC4 (T = Co, Ru, and Os), and their mixed crystals Sc3(Co1-xRux)C4 and Sc3(Ru1-xOsx)C4. Sc3CoC4 exhibits successive phase transitions of charge-density-wave transition at TCDW ~ 140 K, Peierls-like structural transition at Ts ~ 70 K, and superconducting transition at Tc ~ 5 K. Sc3RuC4 and Sc3OsC4 exhibit a phase transition at T* ~ 220 K and 250 K, respectively, which should occur in the low-dimensional electronic structure. For Sc3CoC4, it is revealed by the investigation of the electric and magnetic properties of Sc3(Co1-xRux)C4 that the phase transitions at TCDW, Ts, and Tc exhibit different robustness against Ru doping. For Sc3RuC4 and Sc3OsC4, it is revealed by the investigation of the electric and magnetic properties of Sc3(Ru1-xOsx)C4 that an identical kind of phase transition occurs at T*. Additionally, the present study reveals that the phase transition at T* in Sc3RuC4 and Sc3OsC4 is inherently different from the phase transitions at TCDW, Ts, and Tc in Sc3CoC4.

Phase Transitions in Solid Methane Up to 60 Kbar

1983 ◽  
Vol 22 ◽  
Author(s):  
N.J. Trappeniers
Keyword(s):  
Phase Transition ◽  
Phase Diagram ◽  
Phase Transitions ◽  
Kinetic Energy ◽  
Spherical Shape ◽  
Plastic Crystal ◽  
Cubic Symmetry ◽  
Profound Influence ◽  
Rotational Freedom ◽  
Solid Methane

Solid methane has been a favourite subject for the study of phase transitions ever since the discovery by Clusius [1] of the phase transition α → β at 20.4 K in CH4. The reasons for the sustained interest in solid CH4 may be attributed to the following facts. i. The CH4 molecule has an almost spherical shape with a slight TD anisotropy. As a result, CH4 crystallizes below 90.7 K into a plastic crystal, α, of cubic symmetry, exhibiting almost complete rotational freedom of the molecules. ii. The CH4 molecule is very small in size with a low moment of inertia (I × 1040 g cm2 = 5.34 in CH4 and 10.64 in CD4), leading to a large rotational kinetic energy and related quantum effects at low temperature. iii. The protons in CH4 and the deuterons in CD4 carry a nuclear spin resp. Ip = 1/2 and I. = 1, which gives rise to spin-isomerism. Thus, CH4 has three spin varieties, meta (A1, In = 2), ortho (T2, in = 1) and para (E, In = 0). The isomerism may be expected to have profound influence on the phase diagram of solid methane.

Magnetic Field-Induced Phase Transitions in Ferrofluid Emulsion

1996 ◽  
Vol 10 (23n24) ◽  
pp. 2973-2981 ◽  
Author(s):  
Yun Zhu ◽  
M.L. Ivey ◽  
P. Sheaffer ◽  
J. Pousset ◽  
Jing Liu
Keyword(s):  
Magnetic Field ◽  
Phase Transition ◽  
Phase Diagram ◽  
Phase Transitions ◽  
Liquid Crystal ◽  
Nematic Liquid Crystal ◽  
Volume Fraction ◽  
Emulsion System ◽  
Liquid Crystal Phase ◽  
Critical Fields

Two field-induced phase transition regimes are found in a ferrofluid emulsion system, which are defined by three critical fields, Hc1<HC2<Hc3. The first regime, which starts at Hc1 and finishes at Hc2, is the transition from a gas to induced Nematic liquid crystal phase. In the second regime, or Hc2<H<Hc3, induced Nematic liquid crystal transits to columnar solid structure. A phase diagram is drawn and is explained well by a scaling calculation, which gives Hc1~Φ−1/2, Hc2~Φ−1/4, and Hc3~Φγ exp (πG/Φγ/2), where Φ is the volume fraction, γ=0.172 and G=1.44.

Fundamental Study of Sublimation-Recrystallization Phenomena in PVT-Growth of SiC Single Crystals

2012 ◽  
Vol 717-720 ◽  
pp. 21-24 ◽  
Author(s):  
Tatsuo Fujimoto ◽  
Noboru Ohtani ◽  
Shinya Sato ◽  
Masakazu Katsuno ◽  
Hiroshi Tsuge ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Phase Transitions ◽  
Single Crystals ◽  
Binary Phase Diagram ◽  
Equilibrium Phase ◽  
Quasi Equilibrium ◽  
Fundamental Study ◽  
Binary Phase ◽  
Reaction Processes

Sublimation-recrystallization processes occurring during PVT are investigated from the viewpoint of quasi-equilibrium phase transitions of SiC. In addition to the elemental reaction processes of PVT, other phenomena such as silicon droplet formation and in-situ etching are also discussed based upon the Si-C binary phase diagram, and possible mechanisms are proposed.

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