To establish intrinsic ferromagnetism (FM) and to detect its micro-structural origin (if any), sol-gel derived Zn 0.95 Mn 0.05 O films have been undergone low energy (800 keV) Ar 4+ ion irradiation. The structural, optical, magnetic and micro-structural properties of irradiated and un-irradiated films were investigated by X-ray diffraction (XRD), UV-visible and photoluminescence (PL) spectroscopy, field and temperature dependent magnetization measurements, X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy. All the films exhibit single-phase wurtzite structure and intrinsic FM. The band gap and band tail parameters show systematic variation with fluence of irradiation.PL spectra exhibit a green emission peak (oxygen vacancy) and that has been suppressed significantly for

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Structural, morphological, optical, magnetic properties and chemical state of the constituent elements of 2 at% Mn doped ZnO samples synthesized by solid state reaction and sol-gel techniques were analyzed. The role of chemical or valency state in tuning the magnetic properties has been investigated. X-ray diffractometer, scanning electron microscope, UV-visible and X-ray photoelectron spectroscopes and superconducting quantum interference device vibrating sample magnetometer (SQUID VSM) were employed for investigation. Mn incorporation in ZnO lattice has been shown by single phase wurtzite structured samples. The presence of defects particularly zinc vacancy (V Zn ) has been evidenced from band tailing. Solid state reaction technique derived sample exhibit strong intrinsic ferromagnetism but sol-gel sample didn't show strong ferromagnetic (FM) ordering. Antiferromagnetic (AFM) interaction is present in both samples. The chemical state of Mn is ?2 for solid state reaction technique derived sample whereas for sol-gel technique derived sample it is a mixed chemical state (exists in both ?2 and ?3 states). Finally, the peculiar magnetic behavior has been interpreted from the interaction between V Zn and d-electrons of Mn 2? and Mn 3? states.

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