Calculation of the T-P phase diagrams for the halogenomethane compounds (CCl-=SUB=-4-n-=/SUB=-Br-=SUB=-n-=/SUB=-, n=0, 1, 2, 4) using the mean field theory -=SUP=-*-=/SUP=-

AbstractThe T – P phase diagrams of the halogenomethane compounds (CCl_4 – _ n Br_ n , n = 0, 1, 2, 4) are calculated using a mean field model. By expanding the free energy in terms of the order parameters for the transitions of the liquid (L), rhombohedral (R), face-centered cubic (FCC) and monoclinic (M) phases in those compounds, the phase line equations are derived and they are fitted to the experimental data from the literature. This method of calculating the T – P phase diagram is satisfactory to explain the T – P measurements for the halogenomethane compounds and it can also be applied to two-component systems.

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Mean-field theory of elastic dipoles on a face-centered-cubic lattice

Physical Review B ◽

10.1103/physrevb.48.669 ◽

1993 ◽

Vol 48 (2) ◽

pp. 669-671 ◽

Cited By ~ 4

Author(s):

Robert S. Pfeiffer ◽

Gerald D. Mahan

Keyword(s):

Field Theory ◽

Mean Field Theory ◽

Mean Field ◽

Face Centered Cubic ◽

Cubic Lattice ◽

Face Centered

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A Phase Diagram for the Ice VI–VII–VIII Transitions

Modern Physics Letters B ◽

10.1142/s0217984998000354 ◽

1998 ◽

Vol 12 (08) ◽

pp. 271-279 ◽

Cited By ~ 6

Author(s):

H. Yurtseven ◽

S. Salihoğlu

Keyword(s):

Phase Diagram ◽

Phase Transitions ◽

Field Model ◽

Mean Field ◽

Calculated Phase Diagram ◽

Mean Field Model ◽

Phase Line ◽

Calculated Phase ◽

The Mean ◽

T Phase

In this study we obtain the P–T phase diagram for the ice VI–VII–VIII phase transitions by means of the mean field model developed here. We have fitted the experimentally measured P–T data to our phase line equations. Our calculated phase diagram describes adequately the observed behavior of the ice VI–VII–VIII phase transitions.

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Calculation of the thermodynamic quantities of perovskite metal organics DMAKCr and perovskite HyFe close to the weakly first-order relaxor-like structural transformation using the mean field theory

International Journal of Modern Physics B ◽

10.1142/s0217979219501030 ◽

2019 ◽

Vol 33 (11) ◽

pp. 1950103 ◽

Cited By ~ 4

Author(s):

H. Yurtseven ◽

Ö. Tarı

Keyword(s):

Field Theory ◽

Field Model ◽

Mean Field Theory ◽

Mean Field ◽

Excess Heat Capacity ◽

Mean Field Model ◽

First Order ◽

Entropy Formula ◽

Inverse Susceptibility ◽

The Mean

Weakly first-order or nearly second-order phase transitions occurring in metal–organic frameworks (MOFs), particularly in DMAKCr and perovskite HyFe, are studied under the mean field model by using the observed data from the literature. In this work, mainly thermal and magnetic properties among various physical properties which have been reported in the literature for those MOFs are studied by the mean field theory. By expanding the free energy in terms of the magnetization (order parameter), the excess heat capacity ([Formula: see text]C[Formula: see text]) and entropy ([Formula: see text]S), latent heat (L), magnetization (M) and the inverse susceptibility ([Formula: see text]) are calculated as a function of temperature close to the weakly first-order phase transition within the Landau phenomenological model which is fitted to the experimental data from the literature for C[Formula: see text] (DMAKCr and perovskite HyFe) and for magnetization M (HyFe). Our predictions of the excess heat capacity ([Formula: see text]C[Formula: see text]) and entropy ([Formula: see text]S) agree below T[Formula: see text] with the observed data within the temperature intervals studied for DMAKCr and perovskite HyFe. From our predictions, we find that magnetization decreases continuously whereas the inverse susceptibility decreases linearly with increasing temperature toward the transition temperature in those MOFs as expected for a weakly first-order transition from the mean field model.

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