The donor/acceptor ionic chain (i.e., the D(+)A(-) chain) [Ru-2(2-MeO-4-ClPhCO2)(4)(BTDA-TCNQ)]center dot 2.5(benzene) (1; 2-MeO-4-ClPhCO2- = 2-methoxy-4-chlorobenzoate; BTDA-TCNQ = bis(1,2,5-thiadiazolo)tetracyanoquinodimethane) is a ferrimagnetic chain with S = 3/2 from [Ru-2(II,III)](+) (i.e., D+) and S = 1/2 from BTDA-TCNQ(center dot-) (i.e., A(-)), with J approximate to -100 K, in which long-range antiferromagnetic ordering at T-N = 11 K occurs because interchain antiferromagnetic interactions are critical. Compound 1 undergoes a reversible crystal-to-crystal structural transformation with the elimination/absorption of the crystallization solvent to form the dried compound [Ru-2(2-MeO-4-ClPhCO2)(4)(BTDA-TCNQ)] (1'), which has a higher T-N (14 K). This change is clearly caused by the shortening of the interchain distances because the exchange coupling parameter for the chain is the same in both 1 and 1'. The chain compounds in 1 can be doped with minor diamagnetic [Rh-2(II,III)] species, [{(Ru-2)(1-x)(Rh-2)(x)(2-MeO-4ClPhCO(2))(4)}(BTDA-TCNQ)]center dot 2.5(benzene) (x = 0.03 for Rh-3%; x = 0.05 for Rh-5%; x = 0.16 for Rh-16%), which shifts the T-N to lower temperatures, the magnitude of the shift being dependent on the doping ratio x (T-N = 5.9 K for Rh-3%, T-N = 3.7 K for Rh-5%, and T-N was not observed above 1.8 K for Rh-16%). Drying a doped compound increased its T-N, as was found for 1': T-N = 9.9 K for Rh-3%', T-N = 9.2 K for Rh-5%', and T-N was not observed above 1.8 K for Rh-16%'. T-N had a linear relationship with the doping ratio x of the [Rh-2] species in both the fresh and dried compounds. The T-N linear relationship is associated with the magnitude of the effective magnetic dipole (i.e., the average correlation length) in the chains caused by the [Rh-2] defects as well as naturally generated defects in the synthetic process and with the interchain distances affected by the crystal-to-crystal transformations. These results demonstrate that slightly modifying the short-range correlation lengths, which changes the magnetic dipole magnitudes, strongly affects the bulk antiferromagnetic transition, with key dipole-dipole interactions, in low-dimensional anisotropic systems.