title: Giant spin canting in the S=1/2 antiferromagnetic chain [CuPM(NO3)2(H2O)2]n observed by 13C-NMR.
abstract: We present a combined experimental and theoretical study on copper pyrimidine dinitrate [CuPM(NO3)2(H2O)2]n, a one-dimensional S=1/2 antiferromagnet with alternating local symmetry. From the local susceptibility measured by NMR at the three inequivalent carbon sites in the pyrimidine molecule we deduce a giant spin canting, i.e., an additional staggered magnetization perpendicular to the applied external field at low temperatures. The magnitude of the transverse magnetization, the spin canting of (52+/-4) degrees at 10 K and 9.3 T, and its temperature dependence are in excellent agreement with exact diagonalization calculations.
authors.affiliation: Institut für Metallphysik und Nukleare Festkörperphysik, TU Braunschweig, 38106 Braunschweig, Germany.
authors.forename: A U B
authors.initials: AU
authors.lastname: Wolter
authors.forename: P
authors.initials: P
authors.lastname: Wzietek
authors.forename: S
authors.initials: S
authors.lastname: Süllow
authors.forename: F J
authors.initials: FJ
authors.lastname: Litterst
authors.forename: A
authors.initials: A
authors.lastname: Honecker
authors.forename: W
authors.initials: W
authors.lastname: Brenig
authors.forename: R
authors.initials: R
authors.lastname: Feyerherm
authors.forename: H-H
authors.initials: HH
authors.lastname: Klauss