Spin and charge ordering in La2-xSrxNiO4 with 0.27≤x≤0.5

We report the Sr-concentration dependence of the spin and charge ordering in La2-xSrxNiO4 with 0.27 less than or equal to x less than or equal to 0.5. In this range of the Sr concentration x, the characteristic wave vector epsilon for the magnetic and charge order varies approximately linear in x, i.e. epsilon similar to x. The transition temperature of spin order is always lower than that of stripe order. Two transition temperatures increase for x < x(c) where x(c) = 1/3 and then tend to decrease as x further increases. (C) 1998 Elsevier Science B.V. All rights reserved.