4-Chloro-3-nitro­coumarin: an unusual non-bonding C—Cl...O=C inter­action

In the title compound, 4-chloro-3-nitro-2H-chromen-2-one, C₉H₄ClNO₄, the coumarin core has a planar conformation. The Cl atom accepts one of the bifurcated lone pairs of the keto O atom with sp² hybridization state. The other lone pair is donated to the pyran ring of a neighboring mol­ecule.