PALLADIUM CHEMISTRY IN MOLTEN ALKALI-METAL POLYCHALCOPHOSPHATE FLUXES- SYNTHESIS AND CHARACTERIZATION OF K4PD(PS4)(2), CS4PD(PS4)(2), CS10PD(PSE4)(4), KPDPS4, K2PDP2S6, AND CS2PDP2SE6

The reaction of Pd with a molten mixture of A(2)Q(x)/P(2)Q(5)/Q (A = K , Q = S, x = 3; A = Cs, Q = Se, x = 1) produced the molecular compound s K4Pd(PS4)(2) (I), Cs4Pd(PSe4)(2) (II), and Cs10Pd(PSe4)(4) (III) and the solid-state KPdPS4 (IV), K2PdP2S6 (V), and Cs2PdP2Se6 (VI). Compo unds I-III are air and water sensitive, while IV-VI are air and water stable. All crystals are red or dark red except those of VI, which are black. All of them exhibit a rodlike shape. Compound I crystallizes i n the triclinic space group <P(1)over bar> (No. 2) with a = 6.380(1) A ngstrom, b = 6.897(1) Angstrom, c = 8.999(1) Angstrom, alpha = 87.777( 8)degrees, beta = 81.581(8)degrees, beta = 81.581(8)degrees, gamma = 8 4.429(9)degrees, and Z = 1. Compound II crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 7.491(2) Angstrom, b = 13.340(2 ) Angstrom, c = 10.030(3) Angstrom, beta = 92.21(2)degrees, and Z = 2. Compound III crystallizes in the tetragonal space group <P(4)over bar 2c> (No. 112) with a = b = 13.949(2) Angstrom, c = 11.527(2) Angstrom , and Z = 4. Compound IV crystallizes in the tetragonal space group P4 (2)/mnm (No. 136) with a = b = 8.5337(2) Angstrom, c = 10.5595(5) Angs trom, and Z = 4. Compound V crystallizes in the orthorombic space grou p Pnma (No 62) with a = 15.612(2) Angstrom, b = 7.0724(7) Angstrom, c = 10.080(1) Angstrom, and Z = 4. Compound VI crystallizes in the monoc linic space group C2/c (No. 15) with a = 12.9750(4) Angstrom, b = 8.32 82(2) Angstrom, c = 13.0568(1) Angstrom, beta = 102.940(2)degrees, and Z = 4. Compounds I-m contain the discrete complexes [Pd(PQ(4))(2)](4- ) (Q = S, Se). The mixed salt III contains additional noncoordinating [PSe4](3-) units. The structure of IV consists of Pd(II) in square pla nar sulfur coordination linked by edge-sharing [PS4](3-) tetrahedral g roups to produce one dimensional chains. The structures of V and VI fe ature the [P(2)Q(6)](4-) (Q = S, Se) group coordinated to the square p lanar Pd2+ atoms, yielding [PdP(2)Q(6)](n)(2n-) chains. Physical chara cterization was performed with DTA, far-IR spectroscopy, solid-state U V/vis diffuse reflectance spectroscopy, and single-crystal optical tra nsmission.