Related Experiment Video
Updated: May 13, 2026

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Glycine-Induced Unique Crystal Packing of Octacyanidetungstates With Strong Intermolecular Antiferromagnetic
Tatsuya Konishi1, Koji Nakabayashi1, Kunal Kumar1
1Department of Chemistry, School of Science, The University of Tokyo, Tokyo, Japan.
Abstract:
We report a supramolecular assembly of octacyanidetungstates (S = 1/2) with glycine, Cs3[WV(CN)8](glycine), featuring a one-dimensional columnar structure with a remarkably strong intermolecular antiferromagnetic superexchange interaction of J = -42.41(2) K between adjacent octacyanidetungstates due to their effective packing close to van der Waals contacts. This represents the strongest intermolecular spin-spin interaction reported to date among cyanidemetallates. When exposed to 470 nm light, this compound exhibits a near-infrared emission with a peak at 763 nm originating from the ligand-to-metal charge-transfer excited state of [WV(CN)8]3-. Such emission is notably rare for d1 metal complexes. Additionally, the noncentrosymmetric crystal structure of this compound enables second harmonic generation, emitting second harmonic light at 650 nm when irradiated with 1300 nm incident light.
Related Concept Videos
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Valence Bond Theory
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...

