Integration of Trinuclear Triangle Copper(II) Secondary Building Units in Octacyanidometallates(IV)-Based Frameworks

The design and synthesis of high-dimensional materials based on secondary building blocks (SBUs) play a pivotal role in the further development of functional molecular materials. Herein, the self-assembly of Cu(II) ions, pyrazole (Hpz), and octacyanidometallate(IV) anions in the presence of water produced two new isostructural three-dimensional systems {[Cu-3(mu(3)-OH)(mu-pz)(3)(H2O)(3)](2)[M(CN)(8)]}middotnH(2)O (M = W, 1, and Mo, 2). 1 and 2 consist of trinuclear triangle copper(II) (TTC) SBUs and octacyanidometallates(IV). At room temperature, both assemblies display strong antiferromagnetic interactions within the TTC entities with an average Cu(II)middotmiddotmiddotCu(II) isotropic magnetic coupling constant of about -145 cm(-1). Moreover, a detailed analysis of magnetic data revealed the presence of spin frustration with antisymmetric magnetic exchange-coupling constants of around +32 and +46 cm(-1) for 1 and 2, respectively. Finally, quantum chemical calculations explained their magnetic and optical properties.

Automated summary

The design and synthesis of high-dimensional materials based on secondary building blocks (SBUs) are crucial for the development of functional molecular materials. This study presents the synthesis of two new isostructural three-dimensional systems and investigates their magnetic and optical properties.