A three‐dimensional analysis of the crystal structure of m‐dinitrobenzene

space group l"bn2~. The x and y coordinates determined in a previous investigation have been refined by two-dimensional Fourier methods, the z-coordinates estimated by trial, and all the positional and temperature parameters then refined by three-dimensional least-squares methods. Details (>f the molecular geometry and dimensions, and of the intermolecular separations, have been obtained. The carbon and nitrogon atoms all lie on one plane but the nitro groups are twisted out of this plane about the C-N bonds by about 11% The mean bond lengths are