(E)-1-Phenylethanone semicarbazone

In the title compound, C9H11N3O, the benzene ring is disordered over two positions with refined occupancies of 0.922 (5) and 0.078 (5). The program PLATON [Spek (2009). Acta Cryst. D65, 148-155] recommends the solution in the space group C2/m with a = 7.3050 (3), b = 6.6745 (2), c = 18.3853 (6) angstrom and beta = 96.986 (2)degrees. However, the large number of non-extinct reflections needed to be ignored if C2/m is chosen suggested that the space group is incorrect, even though the R values are lower than that for P2(1)/c. The semicarbazone group is essentially planar, with a maximum deviation of 0.046 (1) angstrom for one of the N atoms. The mean plane of the semicarbazone group forms dihedral angles of 33.61 (8) and 39.1 (9)degrees with the benzene ring of the major and minor components, respectively. In the crystal structure, molecules are linked by intermolecular N-H center dot center dot center dot O hydrogen bonds into extended chains along the c axis. The crystal structure is further stabilized by weak intermolucular C-H center dot center dot center dot pi interactions.