title: Phenyl acridine-9-carboxyl-ate.
abstract: The acridine ring system and the benzene ring in the title compound, C(20)H(13)NO(2), are oriented at a dihedral angle of 6.4 (2)°. The carboxyl group is twisted at an angle of 83.6 (2)° relative to the acridine skeleton. The mol-ecules in the crystal are arranged in stacks along the b axis, with two of the acridine rings involved in multiple π-π inter-actions [centroid-centroid distances in the range 3.536 (2)-3.894 (2) Å]. Stacks arranged parallel are linked via C-H⋯π inter-actions, forming layers in the ac plane that are in contact with adjacent, inversely oriented layers via other C-H⋯π inter-actions, giving rise to double layers. The inversely oriented double layers inter-act dispersively. The acridine units are parallel within the parallel-oriented stacks, but inclined at an angle of 79.6 (2)° in the inversely oriented stacks.
authors: Faculty of Chemistry, University of Gdańsk, J. Sobieskiego 18, 80-952 Gdańsk,  Poland.
authors: Michał
authors: M
authors: Wera
authors: Damian
authors: D
authors: Trzybiński
authors: Karol
authors: K
authors: Krzymiński
authors: Jerzy
authors: J
authors: Błażejowski