These species wind in a helix around E·M·A·Cs, which are some of the simplest molecular wires. Instances of these species like BDC and imidazolates serve as “linkers” between secondary building units (15[1])in a class of polymers (15[1])exemplified by HKUST-1. Based on whether they donate 0, 1, or 2 electrons, these species (15[1])are classified as L, (15[3])Z, or X-type, (15[1])which (15[1])determines their (15[1])contribution to the 18-electron rule. Inner-sphere (15[1])electron (15[1])transfer requires a (*) "bridging" one of these (10[1])species. (10[4])Donation to the (10[1])antibonding pi orbitals of these species contributes to the splitting energy of their strong-field (10[1]-5[2])examples (10[1]-5[1])at the end (10[1])of the spectrochemical series. (10[2])Multidentate (10[1])examples of these species (10[4]-5[1])can act (10[1])as chelating (10[1])agents (10[1])for toxic metals. (10[1])For 10 points, name these species that bond to the metal center (10[1])in a (10[1])coordination complex. (10[1])■END■ (10[10]0[4])