Photoswitching of the spin crossover polymeric material [Fe(Htrz) 2 (trz)](BF 4 ) under continuous laser irradiation in a Raman scattering experiment

•Photoswitching of [Fe(Htrz)2(trz)](BF4) under continuous laser irradiation.•Raman scattering measured outside and inside the hysteresis loop of the material.•Heat diffusion induced by the laser may trigger LS to HS transitions.•Thermal hysteresis loops are modified for laser intensities larger than 0.02mW/μm2.