Three new linear coordination polymers containing Cu(I) and 4,7-phenanthroline (phen) have been synthesized and structurally characterized by single-crystal X-ray diffraction. [Cu(phen)(MeCN)(2)]PF6 (3) and [Cu(phen)(MeCN)]BF4 (4) are prepared from acetonitrile, and [Cu(phen)(BzCN)]BF4 (5) is made from benzonitrile (MeCN = acetonitrile; BzCN = benzonitrile). All of the compounds have linear polymeric structures containing Cu(I) centers coordinated by two bridging 4,7-phenanthroline ligands, with additional coordinated solvent molecules completing the copper coordination sphere. In 3 and 4, when acetonitrile is used, two and one MeCN solvent molecules coordinate to each Cu atom, resulting in a distorted tetrahedral and distorted trigonal geometry, respectively. The major interchain interactions are phenanthroline pi-pi stacks. When benzonitrile is used in 5, the chain-packing motif changes to allow the coordinated benzonitrile ligands to participate in the interchain pi-pi stacking. Crystal data: for [Cu(phen)(MeCN)(2)]PF6 (3), monoclinic, space group P2(1)/c (No. 14), with a = 11.4303(6) Angstrom, b = 11.4954(6) Angstrom, c = 14.0444(7) Angstrom, beta = 99.948(1)degrees, and Z = 4; for [Cu(phen)(MeCN)]BF4 (4), monoclinic, space group P2(1)/c (No. 14), with a = 8.7677(5) Angstrom, b = 11.5140(7) Angstrom, c = 14.8858(9) Angstrom, beta = 96.548(1)degrees, and Z = 4; for [Cu(phen)(BzCN)](2)2BF(4) (5), triclinic, space group P (1) over bar (No. 2), with a = 11.338(1) Angstrom, b = 12.461(1) Angstrom, c = 13.904(1) Angstrom, alpha = 115.909(2)degrees, beta = 100.870(2)degrees, gamma = 92.052(2)degrees, and Z = 2.