Synthesis, Structure and Properties of a New Strong‐Rung Spin Ladder Compound Cu(2‐Ethylpyrazine)Br₂

Abstract

We report the structure and magnetism of a newly synthesized coordination polymer Cu(2-ethylpyrazine)Br 2 . Its crystal structure was determined by both single crystal and powder X-ray diffractions. We find the compound crystallizes in the space group C2 with a ladder structure in which the copper ions are bridged by bromide ions and 2-ethylpyrazine molecules along the rung and rail direction, respectively. The magnetic suscept-ibility is consistent with the strong-rung spin ladder model which yields J rung /k B = À 33.819(1) K, J rail /k B = À 25.206(3) K. The obtained spin gap is Δ = 18.01 K. Both magnetic susceptibility and heat capacity measurements show the absence of low range magnetic order down to 2 K, indicating weak inter-ladder coupling in the compound.