Ferromagnetic properties of rubidium clusters in zeolite LTA

Magnetic and optical properties of Rb clusters in aluminosilicate zeolite L TA are investigated in detail. These clusters are stabilized in supercages arrayed in a simple cubic structure. The average number of s-electrons conf ined in each cluster, n, is changed up to the nearly saturated value simila r to 4.6. At n > 2, the absolute value of the negative Weiss temperature in creases with increasing n. In saturated samples at n similar to 4.6, ferrom agnetic properties are observed below the asymptotic Curie temperature 3 K, but the fraction of the spontaneous magnetization is found to be very smal l and incomplete. Magnetic properties are different from those of K cluster s in LTA, and discussed in relation to residual K cations. (C) 2001 Elsevie r Science B.V. All rights reserved.