Probing the Anisotropic Distortion of Photoexcited Spin Crossover Complexes with Picosecond X-ray Absorption Spectroscopy

Research output: Contribution to journalArticle


For numerous spin crossover complexes, the anisotropic distortion of the first coordination shell around the transition metal center governs the dynamics of the high-spin/low-spin interconversion. However, this structural parameter remains elusive for samples that cannot be investigated with crystallography. The present work demonstrates how picosecond X-ray absorption spectroscopy is able to capture this specific deformation in the photoinduced high-spin state of solvated [Fe(terpy)(2)](2+), a complex which belongs to the prominent family of spin crossover building blocks with nonequivalent metal-ligand bonds. The correlated changes in Fe-N-Axial, Fe-N-Distal, and bite angle N-Distal-Fe-N-Axial extracted from the measurements are in very good agreement with those predicted by DFT calculations in D-2d symmetry. The outlined methodology is generally applicable to the characterization of ultrafast nuclear rearrangements around metal centers in photoactive molecular complexes and nanomaterials, including those that do not display long-range order.


  • Sophie Canton
  • Xiaoyi Zhang
  • Latevi M. Lawson Daku
  • Amanda L. Smeigh
  • Jianxin Zhang
  • Yizhu Liu
  • Carl-Johan Wallentin
  • Klaus Attenkofer
  • Guy Jennings
  • Charles A. Kurtz
  • David Gosztola
  • Kenneth Wärnmark
  • Andreas Hauser
  • Villy Sundström
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Atom and Molecular Physics and Optics
  • Chemical Sciences
Original languageEnglish
Pages (from-to)4536-4545
JournalJournal of Physical Chemistry C
Issue number8
StatePublished - 2014
Publication categoryResearch

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Centre for Analysis and Synthesis (011001266), Chemical Physics (S) (011001060), Department of Chemistry (011001220)