[en] The crystal and magnetic structures of polycrystalline CeDsub(x)(2.2<=x<=3.0) were determined in the temperature range from 1.3 to 380 K by means of conventional and high-resolution time-of-flight neutron diffraction measurements. At high temperatures the structures correspond to FCC (Fm3m) symmetry, with a statistical distribution of deuterium on tetrahedral and octahedral sites (displaced along the directions <111> from the ideal position 1/2, 1/2, 1/2). Whereas CeDsub(x) for x>=2.90 remains approximately cubic down to 1.5 K, second-order phase transitions to ordered structures with tetragonal symmetry (basic translations asub(t) approx. asub(c) approx. 2asub(c), space group 14; in contrast to Titcomb and co-workers) occur at temperatures Tsub(c)=290(3) and 330(5) K for x=2.18 and 2.29 respectively. Between x=2.29 and x=2.96 the magnetic ordering changes from ferromagnetism (Tsub(c)=3.7(2) K, ordered magnetic moment μ(Ce³⁺)=1.1(1)μsub(B) at 1.3 K) to FCC II antiferromagnetism (Tsub(N)=4.2(2) K, μ(Ce³⁺)=0.6(1) μsub(B) at 1.3 K, μparallel to <111>). (author)