Theoretical investigations on physical properties of SrFCuCh (Ch=S and Se)

The first conference on what became the SCTE series was organized by André Michel in Paris in 1965. It was intended to deal with the preparation and Propriétés Thermodynamiques, Physiques et Structurales des Dérivés Semi-Métalliques. The results of experimental as well as theoretical investigations were reported by inorganic chemists, physicists, and crystallographers. Originally, the emphasis was on compounds of the transition metals, the rare earth elements, and the actinoids with the main group elements S, Se, Te, N, P, As, Sb, C, Si, Ge, Sn, and boron. Work on oxides and halides was presented only occasionally. Over the years this has changed gradually. Now investigations of oxides comprise some 10 to 20 % of all reports, especially investigations of compounds with small band gaps and interesting physical properties. The emphasis is shifting from fundamental research to investigations with a view on applications.

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Model-independent description of intermediate-range forces in static spherical bodies

Canadian Journal of Physics ◽

10.1139/p90-086 ◽

1990 ◽

Vol 68 (7-8) ◽

pp. 574-578 ◽

Cited By ~ 1

Author(s):

J. Ponce de Leon

Keyword(s):

Physical Properties ◽

Specific Form ◽

Matter Distribution ◽

Intermediate Range ◽

Theoretical Investigations ◽

Phenomenological Equations ◽

Model Independent

Recent experimental and theoretical investigations suggest the existence of fundamental intermediate-range forces. So far, the behaviour of such forces, in static spherical bodies, has been discussed using particular models, where the matter distribution is restricted to have some specific form. In this work we want to extend the discussion to an arbitrary matter distribution. With this aim, we solve the phenomenological equations that describe intermediate-range forces by quadratures. From the analysis of the physical properties of the solution, we show in detail how the shape of the matter distribution, as well as the range of the field, can influence the magnitude of intermediate-range forces. Our model-independent description allows us to generalize a number of particular results found previously.

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Order Versus Disorder in Chiral Tetrathiafulvalene-Oxazoline Radical-Cation Salts: Structural and Theoretical Investigations and Physical Properties

Chemistry - A European Journal ◽

10.1002/chem.200901980 ◽

2010 ◽

Vol 16 (2) ◽

pp. 528-537 ◽

Cited By ~ 39

Author(s):

Augustinâ€…M. Madalan ◽

CÃ©line RÃ©thorÃ© ◽

Marc FourmiguÃ© ◽

Enric Canadell ◽

Elsaâ€…B. Lopes ◽

...

Keyword(s):

Physical Properties ◽

Radical Cation ◽

Theoretical Investigations ◽

Radical Cation Salts

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Observation of novel charge ordering and spin reorientation in perovskite oxide PbFeO3

Nature Communications ◽

10.1038/s41467-021-22064-9 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xubin Ye ◽

Jianfa Zhao ◽

Hena Das ◽

Denis Sheptyakov ◽

Junye Yang ◽

...

Keyword(s):

Physical Properties ◽

Charge Ordering ◽

Spin Reorientation ◽

Perovskite Oxide ◽

Oxidation States ◽

Ferromagnetic Transition ◽

Detailed Structure ◽

Theoretical Investigations ◽

Spin Moments ◽

Magnetic Sublattices

AbstractPbMO3 (M = 3d transition metals) family shows systematic variations in charge distribution and intriguing physical properties due to its delicate energy balance between Pb 6s and transition metal 3d orbitals. However, the detailed structure and physical properties of PbFeO3 remain unclear. Herein, we reveal that PbFeO3 crystallizes into an unusual 2ap × 6ap × 2ap orthorhombic perovskite super unit cell with space group Cmcm. The distinctive crystal construction and valence distribution of Pb2+0.5Pb4+0.5FeO3 lead to a long range charge ordering of the -A-B-B- type of the layers with two different oxidation states of Pb (Pb2+ and Pb4+) in them. A weak ferromagnetic transition with canted antiferromagnetic spins along the a-axis is found to occur at 600 K. In addition, decreasing the temperature causes a spin reorientation transition towards a collinear antiferromagnetic structure with spin moments along the b-axis near 418 K. Our theoretical investigations reveal that the peculiar charge ordering of Pb generates two Fe3+ magnetic sublattices with competing anisotropic energies, giving rise to the spin reorientation at such a high critical temperature.

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Reassessments of thermo-physical properties of Si-Ti melt at different temperatures

BIBECHANA ◽

10.3126/bibechana.v17i0.26877 ◽

2020 ◽

Vol 17 ◽

pp. 146-155 ◽

Cited By ~ 2

Author(s):

S K Yadav ◽

U Mehta ◽

R K Gohivar ◽

A Dhungana ◽

R P Koirala ◽

...

Keyword(s):

Physical Properties ◽

Surface Segregation ◽

Elevated Temperatures ◽

Liquid Mixture ◽

Compositional Dependence ◽

Theoretical Investigations ◽

Different Temperatures ◽

Frame Work ◽

Literature Database ◽

Thermo Physical Properties

The compositional dependence of thermo-physical properties of Si-Ti liquid alloy has been reassessed using different modeling equations at temperatures 2000 K, 2400 K and 2473 K. The thermodynamic and structural properties of the system have been computed in the frame work of quasi-lattice test. The extent of surface segregation and surface tension of the liquid mixture have been computed using Butler’s equations at afore mentioned temperatures. The results so obtained have been compared with the available literature database. Theoretical investigations shows that the compound forming tendency of the system gradually decreases at elevated temperatures and hence it shows ideal behaviours, as expected. BIBECHANA 17 (2020)

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