Magnetic defects in crystalline Zn(OH)2 and nanocrystalline ZnO resulting from its thermal decomposition

► Crystalline Zn(OH)2 containing trace amounts of substitutional Mn2+ was prepared. ► Mn2+ ions, molecular HO and shallow donor magnetic centers were studied by EPR. ► Decomposition of Zn(OH)2 in nanocrystalline ZnO around 125 °C was investigated. ► The concentration and nature of the magnetic defects variation was monitored by EPR.