Anisotropy in the physical properties of UNiGa under high pressure

The linear thermal expansion, compressibility and magnetostriction of UNiGa have been measured under high pressure. Huge anisotropic behaviors are obs erved in these physical quantities. The linear thermal expansion coefficien ts are alpha(a) similar to 16.10(-6) K-1 along the a-axis and a(c) similar to 5 . 10(-6) K-1 along the c-axis, and the linear compressibilities at roo m temperature are kappa(a) similar to 3.6 . 10(-3) GPa(-1) and kappa(c) sim ilar to 1.7 . 10(-3) GPa(-1) along a-axis and c-axes. respectively. UNiGa o rders antiferromagnetically below T-N = 39 K and shows a metamagnetic trans ition at 4.2 K in magnetic field B-C = 1 T. It is found that T-N decreases and B-C increases with increasing pressure.