title: Crystal structure and magnetism of a well isolated 2D-quantum Heisenberg antiferromagnet, (Quinolinium)(2)CuBr(4).2H(2)O, and its anhydrous form.
abstract: Reaction of quinoline with HBr and CuBr(2) generates a mixture of two compounds, (quinolinium)(2)CuBr(4).2H(2)O (1) and (quinolinium)(2)CuBr(4) (2) for which single-crystal X-ray structures have been solved. Compound 1 crystallizes in the monoclinic space group C2/c as layers of tetrabromocuprate ions which are separated by intervening layers of quinolinium ions. Compound 2 crystallizes in the triclinic space group P1. Magnetic data analysis reveals that 1 behaves as a 2D-quantum Heisenberg antiferromagnet with 2J/k(B) = -6.17(3) K within the layers. High field magnetization data at low temperatures suggests that T(N) must be less than 1.8 K for 1, yielding a figure of merit |k(B)T(N)/2J| < 0.29, which indicates excellent isolation between the layers. Magnetic exchange in compound 2 was much weaker and was fit to a linear chain antiferromagnet with 2J/k(B) = -1.59(3) K.
authors.affiliation: Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, Massachusetts 01610, USA.
authors.forename: Robert T
authors.initials: RT
authors.lastname: Butcher
authors.forename: Mark M
authors.initials: MM
authors.lastname: Turnbull
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Landee
authors.forename: Alex
authors.initials: A
authors.lastname: Shapiro
authors.forename: Fan
authors.initials: F
authors.lastname: Xiao
authors.forename: David
authors.initials: D
authors.lastname: Garrett
authors.forename: Ward T
authors.initials: WT
authors.lastname: Robinson
authors.forename: Brendan
authors.initials: B
authors.lastname: Twamley