title: 4-Nitro-isophthalic acid.
abstract: In the crystal structure of the title compound, C(8)H(5)NO(6), both carboxyl groups are involved in inter-molecular centrosymmetric cyclic O-H⋯O hydrogen-bonding associations, which give a zigzag chain structure extending along (2[Formula: see text]1). Weak π-π stacking inter-actions are also present [minimum ring centroid separation = 3.893 (4) Å].
authors.affiliation: Key Laboratory of Urban and Architectural Heritage Conservation, (Southeast University), Ministry of Education, Nanjing 210096, People's Republic of China, and College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096,  People's Republic of China.
authors.forename: Yang-Hui
authors.initials: YH
authors.lastname: Luo
authors.forename: Mei-Ling
authors.initials: ML
authors.lastname: Pan