Free volume related fluorescent behavior in electron beam irradiated chalcone doped PVA

► Electron irradiation effect on the chalcone doped PVA composite films are studied. ► Optical study shows the irradiation produces defects and molecular ordering. ► XRD diffractograms reveal that the crosslinking enhances the crystallinity. ► PALS suggests the modifications in free volume and chromophore rotational hindrance. ► Enhanced fluorescence by chromophore depends on its hindrance and free volume.