Polymeric Terbium(III) Squarate Hydrate as a Luminescent Magnet

Rina Takano,Takayuki Ishida

doi:10.3390/cryst11101221

Abstract

Polymeric terbium(III) squarate hydrate [{Tb2(C4O4)3(H2O)8}n] was prepared from TbCl3 or Tb2O3 and squaric acid. The crystal structure was determined in a monoclinic Pc space group, and the whole molecular arrangement gives a sandwiched two-dimensional structure. The coordination polyhedra are described as a square antiprism. The solid complex emits green light under UV irradiation at room temperature with the quantum yield of 25%. Although Tb3+ is a non-Kramers ion, the alternating-current magnetic susceptibility showed frequency dependence in a 2000-Oe DC field, and the effective energy barrier for magnetization reorientation was 33(2) K. Thus, [{Tb2(C4O4)3(H2O)8}n] displayed functions of a potential luminescent magnet.

Highlights

Pc space group, and or Tb2 O3 and squaric acid
The crystal structure was determined in a monoclinic Pc space group, the whole molecular arrangement gives a sandwiched two-dimensional structure
The alternating-current (AC) magnetic susceptibilities on Tb-sq were recorded on a Quantum Design PPMS apparatus equipped with an AC/DC magnetic susceptibility option

Summary

Introduction

2–, abbreviated as Squarate, Squarate, a dianion dianion of of 3,4-dihydroxycyclobut-3-ene-1,2-dione. Contrast to transition metal sqmetal salts, Even neutral carbonyl compounds canLn ligate ions. Magnets single-ion(SIMs) magemerge as a next-generation material, especially when exchange coupling is negligible [15]. Ln ions are available for various luminescent materials [17,18], owing to sharp and strong emission, and their coordination compounds have been applied to light-emitting diodes in lighting devices [19,20] and luminescent probes in biology [21]. We aimed at materials showing multifunctionalities by using a Tb3+ ion. In this Communication, the crystal structure of terbium(III) squarate hydrate [{Ln2 (sq) (H2 O)8 }n ] (Ln = Tb; abbreviated as Tbsq hereafter) has been determined for the first time.

Preparation

Structural Analysis

Photoluminescent Measurements

Magnetic Measurements

Results and Discussion

Method