Atomic Volume Effect on Electronic Structure and Magnetic Properties of UGa3 Compound
The magnetic susceptibility x of the itinerant antiferromagnetic compound UGa3 has been studied experimentally under pressure up to 2 kbar in the temperature range 64–300 K. This study reveals a pronounced pressure effect on magnetic properties of UGa3 and the measured pressure derivative of the Néel temperature is found to be dT N/dP=-1.1 K/kbar. In order to analyze the experimental magnetovolume effect, to be specific dln x/dln V, the volume dependent electronic structure of UGa3 has been calculated ab initio in the paramagnetic phase by employing a relativistic full-potential LMTO method. The effect of the external magnetic field was included self-consistently by means of the Zeeman operator, as well as orbital polarization. The calculations have brought out a predominance of itinerant uranium 5f states at the Fermi energy, as well as large and competing orbital and spin contributions to x. The calculated field-induced magnetic moment of UGa3 and its volume derivative compare favorably with our experimental results.
KeywordsMagnetic Susceptibility Magnetic Phase Transition Orbital Polarization Spin Moment Orbital Moment
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