Dielectric and Magnetic Relaxations Exhibited in a 2D Parallel Interpenetrating Frustrated Star Net.

Abstract

Constructing multiple functional geometric frustration magnets is a hot topic in solid state chemistry and material science. Herein, a two-dimensional (2D) parallel interpenetrating "star" net complex [HDMPDA][Fe6 (μ3 -O)2 (μ-O2 CH)15 ] (1) was obtained successfully with HDMPDA (DMPDA=N, N'-dimethyl-1,3-propanediamine) as charge balancer. The dipole reorientation of the rotator [HDMPDA]+ in the complex brings a structure transition which leads dielectric relaxation close to room temperature. Despite strong antiferromagnetic coupling existing between ions in the net, long-range order temperature TN of the complex is suppressed to 4.2 K by geometric frustration. Interestingly, below TN , a canted antiferromagnetic state, accompanied with slow magnetic relaxation, is detected due to the lack of enough magnetic coupling between 2D layers. Thus, 1 is a particular multifunctional magnetic frustration material containing two different types of relaxations.