摘要 本次實驗利用二硒磷酸配位基NH4Se2P(OR)2(dialkyl diselenophosphate ligand)(R=iPr, Et, nPr)(以下簡稱dsep)與銀金屬起始物進行反應,採用的金屬起始物為Ag(CH3CN)4PF6。Ag8正立方體金屬簇錯化合物被合成出來有Ag8(μ8-X)[Se2P(OR)2]6(PF6) (R = Et, X = Cl, 1a, X = Br, 1b, R = nPr, X = Cl, 2a, X = Br, 2b, R = iPr, X = Cl, 3a, X = Br, 3b)以及Ag8(μ8-X)[Se2P(OEt)2]6(X) (X = Cl, 4a, X = Br, 4b)。其中1,2,3使用CH2X2為溶劑,4,5,6則使用ROH為溶劑,皆以Ag(CH3CN)4PF6、dsep、Bu4NX 4:3:1的莫耳比例混合。由單晶X-ray繞射所解出來的結構可知,八個分開銀的陽離子是靠者六個dsep的配位基以及中心的鹵素離子來連結,其中化合物1a-2b伴隨著未配位PF6-的陰離子而化合物4a則與鹵素離子形成鍵結,分子的形狀是被中心鹵素離子扭曲的正力方體。每一個dsep配位基都配位在正立方體所形成的正方形面上的四個銀離子,每一個銀離子都與三個Se及中心的鹵素離子產生鍵結。根據計算所顯示,銀離子與中心鹵素離子的鍵結很弱。
Abstract Ag8 cubic clusters Ag8(μ8-X)[Se2P(OR)2]6(PF6) (R = Et, X = Cl, 1a, X = Br, 1b, R = nPr, X = Cl, 2a, X = Br, 2b, R = iPr, X = Cl, 3a, X = Br, 3b) and Ag8(μ8-X)[Se2P(OR)2]6(X) (R = Et, X = Cl, 4a, X = Br, 4b, R = nPr, X = Cl, 5, R = iPr, X = Cl, 6 ) were isolated from the reaction of [Ag(CH3CN)4](PF6), NH4[Se2P(OR)2], and Bu4NX in a molar ratio of 4:3:1 in CH2X2(1,2,3) and ROH(4). The X-ray structure consists of a discrete cationic cluster in which eight silver ions are linked by six diselenophosphate ligands and a central μ8-Cl or μ8-Br ion with a noncoordinating PF6- anion(1a-2b) or with a coordination halide anion(4a). The shape of the molecule is a halide-centered distorted Ag8 cubic cluster. The dsep ligand exhibits a tetrametallic tetraconnective (μ2, μ2) coordination pattern, and each caps on a square face of the cube. Each silver atom of the cube is coordinated by three selenium atoms and the central chloride or bromide ion. Calculations show very weak bonding interactions exist between μ8-X and Ag atoms of the cube.