Solid-state reactions by manual or mechanical grinding with minimal or no solvent for molecular synthesis called mechanochemistry has blossomed into an important area of research in green synthesis and crystal engineering1.Materials to nanomaterials,metal complexes to coordination polymers(CP)and simple organic to pharmaceutical compounds can be accomplished by this environmentally benign method successfully.Simple grinding of reactants in the solid state also yielded the isolation of materials that are inaccessible otherwise in solution,for example,solid-state interconversions of pillared layer CPs,solvent assisted ligand exchange(SALE),hydrogen-bonded salts,supramolecular catalysis,and grinding assisted changes in the optical properties such as color and luminescence.Some of the interesting results encountered in the authors lab2,3 during mechanochemical grinding such as synthesis of photoreactive CPs,solid state structural transformations accompanied by heat,solvent loss or gain,change in reactivity between single crystals and after grinding into powder will be highlighted in the talk.