%0 Electronic Article %A Basuroy, Krishnayan %A Velazquez Garcia, Jose %A Lalithambika, Sreeju Sreekantan Nair %A Barman, Argha %A Reuss, Torben %A Pompidor, Guillaume %A Grebentsov, Alexander %A Akcaalan, Oender %A Techert, Simone %T Photoinduced Low Spin to High Spin Transition in a [2x2] Fe(II) Metallogrid: Diode Laser-Pumped Photocrystallography at the P11 Beamline in PETRA III, DESY %N arXiv:2508.01734 %M PUBDB-2025-03871 %M arXiv:2508.01734 %D 2025 %X We report on the photoinduced spin crossover (SCO) transition from a 2HS-2LS to a 3HS-1LS state in a [2x2] Fe(II) metallogrid complex using molecular crystals with static photocrystallography at a first ever attempt in the beamline P11 of the PETRA III synchrotron, DESY. A class 3B diode laser was used to induce the transition under controlled irradiation conditions. Structural characterization was achieved through single-crystal X-ray diffraction (SCXRD) measurements post-irradiation, revealing significant changes in average Fe-N distances, consistent with SCO behavior. Our experimental setup enables precise alignment necessary for photo-excitation using a class 3B diode laser along with a compact focusing optics. The longest dimension of the combined setup of the diode head and the focusing optics is not more than 32cm. The setup showcasing the utility of a compact diode laser system which can even be conveniently used in synchrotron-based pump-probe photocrystallography experiments for a wide range of molecular crystals. %K Materials Science (cond-mat.mtrl-sci) (Other) %K Chemical Physics (physics.chem-ph) (Other) %K Optics (physics.optics) (Other) %K FOS: Physical sciences (Other) %F PUB:(DE-HGF)25 %9 Preprint %R 10.3204/PUBDB-2025-03871 %U https://bib-pubdb1.desy.de/record/637645