Selective Photoswitching of the Binuclear Spin Crossover Compound{[Fe(bt)(NCS)2]2(bpm)}into Two Distinct Macroscopic Phases

The low-spin (LS-LS, $S=0$) diamagnetic form of the binuclear spin crossover complex ${[\mathrm{Fe}(\mathrm{bt})(\mathrm{NCS}{)}_{2}{]}_{2}(\mathrm{bpm})}$ was selectively photoconverted into two distinct macroscopic phases at different excitation wavelengths (1342 or 647.1 nm). These long-lived metastable phases have been identified, respectively, as the symmetry-broken paramagnetic form (HS-LS, $\mathrm{S}=2$) and the antiferromagnetically coupled (HS-HS, $S=0$) high-spin form of the compound. The selectivity may be explained by the strong coupling of the primary excited states to the paramagnetic state.

Titelbild: One Shot Laser Pulse Induced Reversible Spin Transition in the Spin-Crossover Complex [Fe(C4H4N2){Pt(CN)4}] at Room Temperature (Angew. Chem. 26/2005)

Cover Picture: One Shot Laser Pulse Induced Reversible Spin Transition in the Spin-Crossover Complex [Fe(C4H4N2){Pt(CN)4}] at Room Temperature (Angew. Chem. Int. Ed. 26/2005)

One Shot Laser Pulse Induced Reversible Spin Transition in the Spin-Crossover Complex [Fe(C4H4N2){Pt(CN)4}] at Room Temperature