［Ag_2（α－Ph_2PPy）_2］_2（NO_3）_4的合成和晶体结构

Synthesis and Crystal Structure of [Ag_2(a-Ph_2PPy)_2]_2(NO_3)_4

ＡｇＮＯ＿３和ａ－ｐｈ＿２ｐｐｙ，（ａ－（Ｃ＿６Ｈ＿５）＿２Ｐ（ＮＣ＿５Ｈ＿５））在加有少量Ｈ＿２Ｏ＿２和ＮａＯＨ的Ｃ＿２Ｈ＿５ＯＨ水溶液中反应生成标题化合物的灰黑色晶体。属四方晶系，空间群Ｐ４＿１，ａ＝１．３００ｎｍ，Ｃ＝４．０７６ｎｍ，ｖ＝６．８８４ｎｍ￣３，Ｚ＝８，Ｄ＿ｃ＝１．６７ｇｃｍ￣（－３），Ｒ＝０．０５９，ｒ＿ω＝０．０７２．每一不对称单元中存在二套独立而结构基本相同的［Ａｇ＿２（ａ－ｐｈ＿２ＰＰｙ）＿２］￣２＋，它的二个Ａｇ原子和二个ａ－ｐｈ＿２ＰＰｙ中－Ｎ－Ｃ－Ｐ－桥的Ｎ，Ｐ原子联接成为一个稳定非共面八员环，而环内Ａｇ，Ａｇ间距分别是０．３１４，０．３ｌ０（ｎｍ），均未成键。不对称单元中的二个八员环通过的Ｏ原子与环上Ａｇ原子的弱成键而具有结构联系。环内还出现了罕见的三配位Ａｇ原子。

Grey─black tetragonal crystals were abtained after reaction of AgNO_3 andPPh_2PPy in a C_2H_5OH/H_2O solution with drops of H_2O_2 and NaOH sOlution. The crystal belongsto space group P4_1,with a=1. 300 nm,c=4.076 nm,u=6.884 nm￣3,z=8,Dc=1.67 g/cm￣3.The final R value is 0.059 and Rw is 0.072. There are two independent [Ag(a-Ph_2PPy)_2]￣2+cations with similar structure in each asymmetric unit. Two Ag atoms and two-N-C-P-p-Brirdidges inPh_2PPy were combined into a steady eight-member-ring which atoms are not on the same plane.Two Ag atoms in each ring are not bonded with distances of 0.3l4,0.310 nm. A rarely seenm-coordinate Ag atom in a ring and two eigh-member-rings are connected with weak bondsbetween Ag atom in the ring and O atoms of