Abstract: Structure and properties of 2,4,7-trinitro-9H-fluorene-9-one charge-transfer complexes with non-linear polycyclic aromatic hydrocarbons acting as donors are studied using quantum chemical calculations in the density functional theory approximation. Formation energies, average distances between the donor and the acceptor planes, and charge transfer from the donor to the acceptor in these complexes are calculated. The crystal and molecular structure of the (1:1) 2,4,7-trinitro-9H-fluorene-9-one complex with phenanthrene (C13H5N3O7·C14H10) is determined by X-ray diffraction analysis. In the crystal of the complex, the donor and acceptor molecules form mixed {–D–A–D–A–}∞ stacks. It is shown that the relative arrangement of the donor and the acceptor in the crystal coincides with that in the most energetically favorable model predicted by calculations. [Figure not available: see fulltext.]. © 2022, Pleiades Publishing, Ltd.