The new planar aromatic tridentate nitrogen ligand 2, 4-bis (3, 5-dimethylpyrazol-1-yl)-6- methoxy-1, 3, 5-triazine (L) has been synthesized and the crystal structure of [EuL (NO3) 3 (H2O)]· L revealed a mononuclear structure with a ten-co-ordinate metal centre; π–π stacking and hydrogen bonding between the co-ordinated and unco-ordinated L molecules sensitized EuIII luminescence.