Photoinduced magnetization in the organic-based magnet Mn(TCNE)(x)* y(CH2Cl2)

Photoinduced magnetization in a magnet based on organic species is reported for the first time. Upon optical excitation in the blue region of spectrum, Mn(tetracyanoethylene)(x)*y(CH2Cl2) (x approximately 2, y is approximately 0.8) exhibits increased magnetic susceptibility at temperatures as high as 75 K, accompanied with photoinduced absorption in the visible and infrared spectral regions. These effects are partially reversible by lower energy visible light and fully reversible by thermal treatment. The results suggest trapping of the photoexcited charge in a metastable state with enhanced exchange interaction.