Specific Heat on Single-crystalline YVO3

The specific heat of single-crystalline YVO3 was measured from 2 K up to 250 K at zero field. The results reveal three transitions, at around 75, 115, and 200 K. The transitions at around 115 K and 200 K show that the phase transition is of the second-order type, whereas at around 75 K, unusual features of the specific heat are found. These unusual features are attributed to the effect of a large change in the volume. The specific heat data were analyzed in terms of a lattice contribution, a Schottky contribution and an excess magnetic contribution at high temperature. The magnetic contribution well above the magnetic ordering temperature is ascribed to short-range interactions due to the presence of strong magnetocrystalline anisotropy. The magnetic entropy considered by using this approach is 9.13 J/mole K which is close to the theoretical estimate for the S = 1 system.

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Thermal and magnetic properties of ferric methylammonium sulphate

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1956.0186 ◽

1956 ◽

Vol 237 (1210) ◽

pp. 404-412 ◽

Cited By ~ 11

Keyword(s):

Magnetic Properties ◽

Magnetic Susceptibility ◽

Specific Heat ◽

Magnetic Anomaly ◽

Ground State ◽

Magnetic Contribution ◽

Lattice Contribution ◽

Magnetic Cooling ◽

Maximum Value ◽

Other Substances

The specific heat and magnetic susceptibility of ferric methylammonium sulphate have been measured at temperatures between 0·17 and 20°K. The specific heat has been analyzed into a lattice contribution and a magnetic anomaly. It is shown that the magnetic contribution to the specific heat can be accounted for almost entirely by the Schottky anomaly due to the Stark splittings of the ground state of the Fe 3+ ions, previously determined by Bleaney & Trenam. These splittings are unusually large in this salt, with the result that the specific heat is very large at temperatures near 1°K, reaching a maximum value of 1·1 cal/mole at 0·33°K. The salt should therefore be useful for magnetic cooling experiments in which other substances are to be kept below 1°K for prolonged periods.

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Lattice Dynamics and Thermal Expansion of Thulium

Zeitschrift für Naturforschung A ◽

10.1515/zna-1979-0212 ◽

1979 ◽

Vol 34 (2) ◽

pp. 200-206 ◽

Cited By ~ 1

Author(s):

R. Ramji Rao ◽

A. Rajput

Keyword(s):

Thermal Expansion ◽

Specific Heat ◽

Lattice Dynamics ◽

Earth Metal ◽

Magnetic Ordering ◽

Magnetic Contribution ◽

Magnetic Entropy ◽

Lattice Heat Capacity ◽

Lattice Specific Heat ◽

Lattice Heat

Abstract The lattice dynamics, lattice specific heat and thermal expansion of the rare-earth metal thulium are worked out applying a model based on Keating’s method. A frequency distribution function involving 50,880 frequencies has been employed. Using the calculated lattice heat capacity, the experimental Cp data of thulium are analysed to get the magnetic contribution to the specific heat in this metal. The energy of magnetic ordering and the magnetic entropy increase involved in the transition from the ordered antiferromagnetic phase to the disordered paramagnetic phase are evaluated. The lattice parameters and volume of thulium are also calculated as a function of hydrostatic pressure and compared with the experimental results

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Magnetocaloric and Thermal Properties of Ho(Co1–xSix)2 Compounds

Zeitschrift für Naturforschung B ◽

10.1515/znb-2007-0714 ◽

2007 ◽

Vol 62 (7) ◽

pp. 965-970 ◽

Cited By ~ 6

Author(s):

Vladimír Sechovský ◽

Denys Vasylyev ◽

Jan Prokleška

Keyword(s):

Magnetic Field ◽

Specific Heat ◽

Magnetocaloric Effect ◽

Magnetic Phase ◽

Magnetic Ordering ◽

Entropy Change ◽

Specific Heat Data ◽

Magnetic Refrigerant ◽

Ordering Transition ◽

Heat Data

Abstract The specific heat and thermal conductivity of HoCo2 and Ho(Co0.95Si0.05)2 were measured as functions of temperature in several constant magnetic fields up to 8 T. From a specific-heat data analysis the isothermal entropy change and the magnetocaloric effect (MCE) have been evaluated in a wide temperature range for several values of the applied magnetic field. The considerable values of the magnetocaloric effect in the vicinity of the magnetic ordering transition are qualifying both compounds as suitable for magnetic refrigeration purposes. The magnetic phase transition temperature (TC) increases from 77 K for HoCo2 to 103 K for Ho(Co0.95Si0.05)2 while the large MCE in the vicinity of TC is maintained, which demonstrates ways of tuning the operating temperatures of the magnetic refrigerant.

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Nuclear specific heat of bccHe3near the magnetic ordering transitions

Physical Review B ◽

10.1103/physrevb.36.6853 ◽

1987 ◽

Vol 36 (13) ◽

pp. 6853-6870 ◽

Cited By ~ 56

Author(s):

Dennis S. Greywall ◽

Paul A. Busch

Keyword(s):

Specific Heat ◽

Magnetic Ordering ◽

Ordering Transitions

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Specific heat data of high-Tc superconductors: Lattice and electronic contributions

Solid State Communications ◽

10.1016/0038-1098(89)90049-5 ◽

1989 ◽

Vol 69 (6) ◽

pp. 625-629 ◽

Cited By ~ 36

Author(s):

J.E. Gordon ◽

M.L. Tan ◽

R.A. Fisher ◽

N.E. Phillips

Keyword(s):

Specific Heat ◽

High Tc Superconductors ◽

Specific Heat Data ◽

High Tc ◽

Heat Data

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PROTON MAGNETIC RESONANCE IN PARAMAGNETIC AND ANTIFERROMAGNETIC CoCl2∙6H2O

Canadian Journal of Physics ◽

10.1139/p64-062 ◽

1964 ◽

Vol 42 (4) ◽

pp. 657-677 ◽

Cited By ~ 32

Author(s):

E. Sawatzky ◽

M. Bloom

Keyword(s):

Magnetic Resonance ◽

Crystal Orientation ◽

Applied Field ◽

Field Approximation ◽

Order Effects ◽

Zero Field ◽

Proton Resonance ◽

Specific Heat Data ◽

Thermodynamic Variables ◽

Heat Data

The transition temperature TN of CoCl2∙6H2O was measured as a function of applied field and crystal orientation using the proton resonance lines, since they are very sensitive functions of temperature near TN. TN was found to be a complicated function of the applied field and crystal orientation, which cannot be described by the molecular field approximation. The transition is gradual rather than sudden and coexistence of the NMR spectra associated with the paramagnetic and antiferromagnetic phases was observed over a temperature region of about 10−2 °K. Short-range order effects were observed near TN in the form of anomalous broadening of the magnetic resonance lines. The magnetic susceptibility in zero field was measured along the preferred axis of antiferromagnetic alignment. This, together with specific heat data from published literature, was used to show a mutual consistency between thermodynamic variables and the dependence of TN on H in low fields as obtained by NMR. The treatment follows that of Buckingham and Fairbank for the λ transition in liquid helium. The sublattice magnetization in the antiferromagnetic phase was measured as a function of temperature. It was found to depend logarithmically on (TN – T), for all values of applied field.

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Influence of Crystallite Size on the Magnetic Order in Semiconducting ZnCr2Se4 Nanoparticles

Materials ◽

10.3390/ma12233947 ◽

2019 ◽

Vol 12 (23) ◽

pp. 3947 ◽

Cited By ~ 2

Author(s):

Ewa Malicka ◽

Małgorzata Karolus ◽

Tadeusz Groń ◽

Adrian Gudwański ◽

Andrzej Ślebarski ◽

...

Keyword(s):

Single Crystal ◽

Specific Heat ◽

Spin Glass ◽

Crystallite Size ◽

Magnetic Order ◽

Ac Susceptibility ◽

High Energy ◽

Zero Field ◽

Bulk Single Crystal ◽

Field Cooling

Structural, electrical, magnetic, and specific heat measurements were carried out on ZnCr2Se4 single crystal and on nanocrystals obtained from the milling of this single crystal after 1, 3, and 5 h, whose crystallite sizes were 25.2, 2.5, and 2 nm, respectively. For this purpose, the high-energy ball-milling method was used. The above studies showed that all samples have a spinel structure, and are p-type semiconductors with less milling time and n-type with a higher one. In turn, the decrease in crystallite size caused a change in the magnetic order, from antiferromagnetic for bulk material and nanocrystals after 1 and 3 h of milling to spin-glass with the freezing temperature Tf = 20 K for the sample after 5 h of milling. The spin-glass behavior for this sample was derived from a broad peak of dc magnetic susceptibility, a splitting of the zero-field-cooling and field-cooling susceptibilities, and from the shift of Tf towards the higher frequency of the ac susceptibility curves. A spectacular result for this sample is also the lack of a peak on the specific heat curve, suggesting a disappearance of the structural transition that is observed for the bulk single crystal.

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