中性磷(膦)类稀土萃合物的结构研究(Ⅳ)——四(三苯基氧膦)高氯酸钕合二丙酮的合成和结构

合成了四(三苯基氧膦)高氯酸稀土络合物。有关鉴定和元素分析表明,络合物的分子式为Ln(ClO_4)_3·4PhPO,其中Ln=La、Pr、Nd、Sm、Eu。用X射线单晶衍射法测定了CNd(ClO_4)_2·4Ph_3PO]ClO_4·2CH_3COCH_3的晶体和分子结构,该晶体属单斜晶系、P2_(1/c)空间群:a=13.469(5)、b=19.540(8)、c=28.437(9)、β=90.79(3)°、V=7483(5)(?)~3,Z=4。钕与八个氧配位,其中四个氧来自四个三苯基氧膦的膦酰基,四个氧由两个双齿配位的高氯酸根提供,组成了[Nd(ClO_4)_24Ph_3PO]~+络阳离子,它与外界的另一个ClO_4~-以静电相互作用形成分子。溶剂分子CH_3COCH_3不与钕成键。钕的配位多面体具有D_(2d)P_(2m)对称性,是一个不规则的三角十二面体。     

三苯基氧化膦与氯金酸形成的萃合物晶体的合成、特性和结构

本文报道了三苯基氧化膦与氯金酸形成的两种配合物晶体的合成、特性和结构.由元素分析及谱学特性确定了萃合物的组成分别为HAuCl_4·2(C_6H_5)_3PO(1)和HAuCl_4·H_2O·4(C_6H_5)_3PO(2).X射线结构分析确定了两种单晶的结构.晶体(1)属于单斜晶系,空间群为C2/c,组成化学式为[(Ph_3PO)_2H]·AuCl_4,其中存在有对称氢键.晶体(2)属于三斜晶系,空间群为PI,组成化学式为(H_3O)·[AuCl_4]·4Ph_3PO,其中存在有分叉氢键.     

四(三苯基氧膦)高氯酸钕合乙醇配合物的合成及结构测定

合成了Nd(ClO_4)_3·4phP=O·C_2H_5OH配合物,用四园衍射仪测定了它的分子及晶体结构,此晶体属三斜晶系P1空间群,晶胞参数为:a=13.475(61)A;b=15.003(15)A;c=18.697(15)A;α=85.44(7);β=78.49(24)°;γ=83.13(26)°;V=3671.2A,分子由99个非氢原子组成,实际上分子可分为三个部分即:配阳离子[Nd(ClO_4)_2·4phPO]~+;阴离子ClO_4和溶剂合分子C_2H_5OH配阳离子的钕与八个氧配位,四个氧来自双齿配位的ClO_4,四个氧来自四个ph_3PO,八个配位氧组成三角十二面体。 中性膦(磷)类化合物包括(RO)_3P=O和R_3P=O是一类重要的萃取剂。工业上已应用的TBP和TOPO都属于这一类。为了研究这类萃取剂在不同底液中萃取行为之所以不同的内在因素,我们制备了不同希土盐类与三苯基氧膦的配合物,并对它们进行了结构测定。已知的中性氧膦希土配合物中进行过结构测定的有Ce(NO)·2phP=O、Nd(NO)_2·2php=O·C_2HOH、La(NO_3)_3·3php=O·C_2H_5OH·CHCl_3和Nd(NCS)·4php=O。这些配合物晶体及分子结构各异,这表明了三苯基氧膦在形成配合物时的复杂性。本文报导的Nd(ClO_4)·4phP=O·C_2H_5OH实际上是由三部分组成;即[Nd(ClO_4)_2·4phP=O]~+外界的ClO_4和溶剂合分子。这在中性配体与高氯酸希土形成的配合物中时有发现。已知结构的     

镧系双亚砜络合物的研究(Ⅲ)——镧系高氯酸盐的双(正-辛基亚砜)乙烷络合物

合成了12个镧系高氯酸盐的高熔点双(正-辛基亚砜)乙烷(α-BOSE)络合物。元素分析、摩尔电导、红外光谱、热谱和电子光谱等研究证实,络合物组成为:Ln(ClO_4)_3(BOSE)_3·nH_2O(Ln=La、Sm、Gd、Ho、Tm、n=0;Ln=Ce、Pr、Nd、Eu、n=2)和Ln_2(ClO_4)_6(BOSE)_5·4H_2O(Ln=Dy、Er)以及Yb(ClO_4)_3(BOSE)_2·2H_2O。络合物中的BOSE均通过>S=O基团的氧原子与镧系离子结合。随镧系离子半径减小,络合物的配位数、共价参数和热稳定性等均有减小倾向。     

三元体系LaX3—PIAP—H2O（X^—=ClO4^—,NO3^—,Cl^—）（30℃）的相平衡

测定了三个三元体系LaX_3-PIAP-H_2O（X~- = ClO_4~-，NO_3~-，Cl~-， PIAP为4－（邻苯二甲酰基）亚基安替比林）在30℃时的溶解度。研究发现La (NO_3)_3-PIAP-H_2O和LaCl_3-PIAP-H_2O体系均为简单共饱型；La(ClO_4)_3- PIAP-H_2O体系有一个新固相形成，其组成为La(PIAP)_3（ClO_4）_3·4H_2O和体 系均为简单共饱型；La(ClO_4)_3-PIAP-H_2O体系的相平衡研究结果，合成了相应 的镧系配合物Ln(PIAP)_3(ClO_4)_3·4H_2O(Ln = La, Pr, Nd, Sm, Gd, Yb)，通 过化学分析、元素分析TG-DTG'IR谱和密度对化合物进行了表征。     

稀土与不同端基直链聚醚配合物的合成及其NMR研究

合成了稀土高氯酸盐分别与一缩二乙二醇二甲醚(EO_2Me_2)和一缩二乙二醇-二-(邻甲氧基苯基)醚[EO_2(MeOP)_2]形成的两系列17种新的配合物,经元素分析、IR、NMR表征,确定配合物组成为Ln_3(ClO_4)_9(EO_2Me_2)_5·18H_2O(Ln=La,Pr,Nd)和Ln(ClO_4)_3EO_2Me_2·8H_2O(Ln=Sm,Eu,Gd,Tb,Dy,Ho,Er,Yb,Y)及Ln(ClO_4)_3EO_2(MeOP)_2·6H_2O(Ln=La,Pr,Nd,Eu,Gd).讨论了它们的NMR及光谱等性质,研究了不同端基直链聚醚对配位作用的影响。     

希土与芳香胺及其氮氧化物形成配合物的研究 X.镧系元素高氯酸盐与2,2''''—二喹啉甲烷固态配合物的合成及性质

本文报道了除钜以外的镧系元素高氯酸盐与2,2′-二喹啉甲烷(Biqm)所形成的新型固体配合物Ln(Biqm)_2(ClO_4)_3·nH_2O(n=0～4)的合成方法,以及通过元素分析、红外光谱、紫外光谱、差热-热重分析、X射线物相分析和电导测定等手段,对配合物的组成和性质所进行的研究结果,推测该类配合物的结构式为:[Ln(Biqm)_2ClO_4]·(ClO_4)_2·nH_2O。     

HPMTFP与1,10—菲罗啉(Phen)等中性萃取剂对Co(Ⅱ)的协同萃取

本文研究了以1-苯基-3-甲基-4-4-三氟乙酰基吡唑啉酮-5(HPMTFP)与1,10菲罗啉(Phen)。三辛基氧磷(TOPO)、三苯基氧磷(Ph_3PO)、三丁基磷酸酯(TBP)和二戊基亚砜(DASO)的氯仿溶液对CO(Ⅱ)的协同萃取.协萃图上发现,HPMTFP与Phen协萃效应显著,与TOPO、Ph_3PO协萃效应较小,而与TBP、DASO基本上无协萃效应.本文由协萃图数据斜率分析和求协萃反应平衡常数的方法,推断萃合物组成为Co(PMTFP)_2·B(B分别为Phen、TOPO、Ph_3PO),求得的各协萃反应的平衡常数如下:Co~(2+)+2HPMTFP_(0)+Phen_(0) Co(PMTFP)_2·Phen_(0)+2H~+ β_(12)=9.57Co~(2+)+2HPMTFP_(0)+TOPO_(0) Co(PMTFP)_2·TOPO_(0)+2H~+ β_(12)=9.56×10~(-3)Co~(2+)+2HPMTFP_(0)+PH_3PO_(0) Co(PMTFP)_2·PH_3PO_(0)+2H~+ β_(12)=5.01×10~(-3)根据模拟萃合物Co(PMTFP)_2·2C_2H_5OH和萃合物Co(PMTFP)_2·Phen的单晶X-射线结构研究结果,讨论了萃合物的结构和产生协萃效应的原因。     

稀土高氯酸盐与1,10—二氮杂菲—1—氧化物的配合物研究

本研究合成出十三种稀土高氯酸盐与phenNO的配合物。元素分析确定配合物的组成为RE(phenNO)_4(ClO_4)_3·H_2O(RE=La、Pr、Nd,Sm～Lu)。对该系列配合物的红外光谱、紫外光谱、荧光光谱、热谱、摩尔电导等性质进行了研究。     

四(三苯基氧化膦)二氯稀土(Ⅲ)-三氯化铜(Ⅱ)配合物的合成和谱学性质

合成了通式为[LnCl_2(Ph_aPO)_4][CuCl_3](Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Y)的12种新配合物,X射线衍射结构分析证实[GdCl_2(Ph_2PO)_4][CuCl_3]中Gd(Ⅲ)为六配位畸变八面体形,Cu(Ⅱ)为三配位平面三角形.测定了所有配合物的红外光谱、~(31)P NMR和Cu(Ⅱ)的顺磁共振谱,并对[LnCl_2(Ph_3PO)_4][CuCl_3]的生成进行了讨论.     

Conversion of phenyl-substituted cyclopentadienes to pyrylium cations

Phenyl-substituted cyclopentadienes are proved to form phenylated pyrylium cations in the presence of silver(I) perchlorate by insertion of an oxygen atom into the cyclopentadiene-ring. Three phenylated pyrylium compounds, [(Ph(5)C(5)O(+))(ClO(4)(-))](2)(CH(2)Cl(2)) (1), Ag(ClO(4))(H(2)O)(Ph(4)HC(5)O(+)) (ClO(4)(-)) (2), and (Ph(3)H(2)C(5)O(+))(ClO(4)(-)) (3) have been synthesized and characterized. A possible reaction pathway and formation mechanism of the pyrylium cation are proposed and discussed.     

Platinum(II) complexes with pi-conjugated, naphthyl-substituted, cyclometalated ligands (RC N N): structures and photo- and electroluminescence

The crystal structures and photophysical properties of mononuclear [(RC N N)PtX](ClO4)n ((RC N N)=3-(6'-(2'-naphthyl)-2'-pyridyl)isoquinolinyl and derivatives; X=Cl, n=0; X=PPh(3) or PCy(3), n=1), dinuclear [(RC N N)2Pt2(mu-dppm)](ClO4)2 (dppm=bis(diphenyphosphino)methyl) and trinuclear [(RC N N)3Pt3(mu-dpmp)](ClO4)3 (dpmp=bis(diphenylphosphinomethyl)phenylphosphine) complexes are presented. The crystal structures show extensive intra- and/or intermolecular pipi interactions; the two (RC N N) planes of [(RC N N)2Pt2(mu-dppm)](ClO4)2 (R=Ph, 3,5-tBu2Ph or 3,5-(CF3)2Ph) are in a nearly eclipsed configuration with torsion angles close to 0 degrees. [(RC N N)PtCl], [(RC N N)2Pt2(mu-dppm)](ClO4)2, and [(RC N N)3Pt3(mu-dpmp)](ClO4)3 are strongly emissive with quantum yields of up to 0.68 in CH2Cl2 or MeCN solution at room temperature. The [(RC N N)PtCl] complexes have a high thermal stability (T(d)=470-549 degrees C). High-performance light-emitting devices containing [(RC N N)PtCl] (R=H or 3,5-tBu2Ph) as a light-emitting material have been fabricated; they have a maximum luminance of 63,000 cd m(-2) and CIE 1931 coordinates at x=0.36, y=0.54.     

二甲基甲酰胺中四种钕盐的电导

通过电导测量研究了四种钕盐：Nd(CF3SO3)3、Nd(ClO4)3、Nd(NO3)3和NdCl3在极性非质子溶剂DMF中的电导性质.利用线性拟合方法求得在25 ℃下Nd(CF3SO3)3和Nd(ClO4)3的极限摩尔电导率分别为278.8和 280.7 S•cm2•mol－1.用间接方法求得Nd(NO3)3 与NdCl3 的极限摩尔电导率分别为297.2和287.3 S•cm2 •mol－1.在25～65 ℃温度范围内，Nd(CF3SO3)3和Nd(ClO4)3的电导率随温度呈线性变化. Nd(NO3)3和NdCl3的电导行为表现出明显的离子缔合.     

First row divalent transition metal complexes of aryl-appended tris((pyridyl)methyl)amine ligands: syntheses, structures, electrochemistry, and hydroxamate binding properties

Divalent manganese, cobalt, nickel, and zinc complexes of 6-Ph(2)TPA (N,N-bis((6-phenyl-2-pyridyl)methyl)-N-((2-pyridyl)methyl)amine; [(6-Ph(2)TPA)Mn(CH(3)OH)(3)](ClO(4))(2) (1), [(6-Ph(2)TPA)Co(CH(3)CN)](ClO(4))(2) (2), [(6-Ph(2)TPA)Ni(CH(3)CN)(CH(3)OH)](ClO(4))(2) (3), [(6-Ph(2)TPA)Zn(CH(3)CN)](ClO(4))(2) (4)) and 6-(Me(2)Ph)(2)TPA (N,N-bis((6-(3,5-dimethyl)phenyl-2-pyridyl)methyl)-N-((2-pyridyl)methyl)amine; [(6-(Me(2)Ph)(2)TPA)Ni(CH(3)CN)(2)](ClO(4))(2) (5) and [(6-(Me(2)Ph)(2)TPA)Zn(CH(3)CN)](ClO(4))(2) (6)) have been prepared and characterized. X-ray crystallographic characterization of 1A.CH(3)()OH and 1B.2CH(3)()OH (differing solvates of 1), 2.2CH(3)()CN, 3.CH(3)()OH, 4.2CH(3)()CN, and 6.2.5CH(3)()CN revealed mononuclear cations with one to three coordinated solvent molecules. In 1A.CH(3)()OH and 1B.2CH(3)()OH, one phenyl-substituted pyridyl arm is not coordinated and forms a secondary hydrogen-bonding interaction with a manganese bound methanol molecule. In 2.2CH(3)()CN, 3.CH(3)()OH, 4.2CH(3)()CN, and 6.2.5CH(3)()CN, all pyridyl donors of the 6-Ph(2)TPA and 6-(Me(2)Ph)(2)TPA ligands are coordinated to the divalent metal center. In the cobalt, nickel, and zinc derivatives, CH/pi interactions are found between a bound acetonitrile molecule and the aryl appendages of the 6-Ph(2)TPA and 6-(Me(2)Ph)(2)TPA ligands. (1)H NMR spectra of 4 and 6 in CD(3)NO(2) solution indicate the presence of CH/pi interactions, as an upfield-shifted methyl resonance for a bound acetonitrile molecule is present. Examination of the cyclic voltammetry of 1-3 and 5 revealed no oxidative (M(II)/M(III)) couples. Admixture of equimolar amounts of 6-Ph(2)TPA, M(ClO(4))(2).6H(2)O, and Me(4)NOH.5H(2)O, followed by the addition of an equimolar amount of acetohydroxamic acid, yielded the acetohydroxamate complexes [((6-Ph(2)TPA)Mn)(2)(micro-ONHC(O)CH(3))(2)](ClO(4))(2) (8), [(6-Ph(2)TPA)Co(ONHC(O)CH(3))](ClO(4))(2) (9), [(6-Ph(2)TPA)Ni(ONHC(O)CH(3))](ClO(4))(2) (10), and [(6-Ph(2)TPA)Zn(ONHC(O)CH(3))](ClO(4))(2) (11), all of which were characterized by X-ray crystallography. The Mn(II) complex 8.0.75CH(3)()CN.0.75Et(2)()O exhibits a dinuclear structure with bridging hydroxamate ligands, whereas the Co(II), Ni(II), and Zn(II) derivatives all exhibit mononuclear six-coordinate structures with a chelating hydroxamate ligand.     

Anion-directed self-assembly of lanthanide-notp compounds and their fluorescence, magnetic, and catalytic properties

Reactions of 1,4,7-triazacyclononane-1,4,7-triyl-tris(methylenephosphonic acid) [notpH(6), C(9)H(18)N(3)(PO(3)H(2))3] with different lanthanide salts result in four types of Ln-notp compounds: [Ln{C(9)H(20)N(3)(PO(3)H)(2)(PO(3))}(NO(3))(H(2)O)].4H2O (1), [Ln = Eu (1 Eu), Gd (1 Gd), Tb (1 Tb)], [Ln{C(9)H(20)N(3)(PO(3)H)(2)(PO(3))}(H2O)]Cl.3H2O (2) [Ln = Eu (2 Eu), Gd (2 Gd), Tb (2 Tb)], [Ln{C(9)H(20)N(3)(PO(3)H)(2)(PO(3))}(H2O)]ClO4.8H2O, (3) [Ln = Eu (3 Eu), Gd (3 Gd)], and [Ln{C(9)H(20)N(3)(PO(3)H)(2)(PO(3))}(H2O)]ClO4.3H2O (4), [Ln = Gd (4 Gd), Tb (4 Tb)]. Compounds within each type are isostructural. In compounds 1, dimers of {Ln2(notpH4)2(NO3)2(H2O)2} are found, in which the two lanthanide atoms are connected by two pairs of O-P-O and one pair of mu-O bridges. The NO3- ion serves as a bidentate terminal ligand. Compounds 2 contain similar dimeric units of {Ln2(notpH4)2(H2O)2} that are further connected by a pair of O-P-O bridges into an alternating chain. The Cl- ions are involved in the interchain hydrogen-bonding networks. A similar chain structure is also found in compounds 3; in this case, however, the chains are linked by ClO4- counterions through hydrogen-bonding interactions, forming an undulating layer in the (011) plane. These layers are fused through hydrogen-bonding interactions, leading to a three-dimensional supramolecular network with large channels in the [100] direction. Compounds 4 show an interesting brick-wall-like layer structure in which the neighboring lanthanide atoms are connected by a pair of O-P-O bridges. The ClO4- counterions and the lattice water molecules are between the layers. In all compounds the triazamacrocyclic nitrogen atoms are not coordinated to the Ln(III) ions. The anions and the pH are believed to play key roles in directing the formation of a particular structure. The fluorescence spectroscopic properties of the Eu and Tb compounds, magnetic properties of the Gd compounds, and the catalytic properties of 4 Gd were also studied.     

铀的三元协萃规律研究-HTTA-HPMBA-(C8H5)4AsCl三元协萃高氯酸铀酰的机理

本文研究α-噻吩甲酰三氟丙酮(HTTA),1-苯基-3-甲基-4-苯甲酰基-5吡唑啉酮(HPMBP)与四苯基砷氯(C5H5)4AsCl的氯仿溶液从高氯酸中萃取U(VI).该体系属螯合,离子缔合AAC类,测定了其二元及三元协同萃取体系平衡常数.用亚甲基蓝光度法测定了萃合物中ClO4^-的存在,用斜率法确定二元协萃物组成为(C6H5)4As^+[UO2(ClO4)(TTA)2]^-和C6H5)4As^+[UO2(ClO4)(PMBP)2]^-三元协萃配合物为(C6H5)4As^+[UO2(ClO4)(TTA)(PMBP)]^-.     

Temperature dependence of the crystal structure and g-values of [(HC(Ph2PO)3)2Cu](ClO4)2.2H2O: influence of dynamic Jahn-Teller coupling and lattice strain interactions

The temperature dependence of the X-ray crystal structure and powder EPR spectrum of [(HC(Ph(2)PO)(3))(2)Cu](ClO(4))(2).2H(2)O is reported, and the structure at room temperature confirms that reported previously. Below approximately 100 K, the data imply a geometry with near elongated tetragonal symmetry for the [(HC(Ph(2)PO)(3))(2)Cu](2+) complex, but on warming the two higher Cu-O bond lengths and g-values progressively converge, and by 340 K the bond lengths correspond to a compressed tetragonal geometry. The data may be interpreted satisfactorily assuming an equilibrium among the energy levels of a Cu-O(6) polyhedron subjected to Jahn-Teller vibronic coupling and a lattice strain. However, agreement with the experiment is obtained only if the orthorhombic component of the lattice strain decreases to a negligible value as the temperature approaches 340 K.     

General-acid-catalyzed reactions of hypochlorous acid and acetyl hypochlorite with chlorite ion

The rate of oxidation of ClO2- by HOCl is first order in each reactant and is general-acid catalyzed. In the initial steps of the proposed mechanism, a steady-state intermediate, HOClOClO-, forms (k1 = 1.6 M-1 s-1) and undergoes general-acid (HA)-catalyzed reactions (k2HA) to generate a metastable intermediate, ClOClO. Values of k2HA/k-1 are 1.6 x 10(4) M-1 (H3O+), 20 M-1 (HOAc), and 8.5 M-1 (H2PO4-). Subsequent competitive reactions of ClOClO with ClO2- (k3) to give 2ClO2 and with OH- (k4OH) and other bases (k5B) to give ClO3- are very rapid. The relative yields of these products give k4OH/k3 = 1.3 x 10(5), k5HPO4/k3 = 0.20, and k5OAc/k3 = 0.06. At low pH and low buffer concentrations, the apparent yield of ClO2, based on 2ClO2 per initial HOCl, reaches 140%. This anomaly is attributed to the induced disproportionation of ClO2- by ClOClO to give ClO3- and additional HOCl. A highly reactive intermediate, ClOCl(O)OClO-, is proposed that can undergo Cl-O bond cleavage to give 2ClO2 + Cl- via one path and ClO3- + 2HOCl via another path. The additional HOCl recycles in the presence of excess ClO2- to give more ClO2. Ab initio calculations show feasible structures for the proposed reaction intermediates. Acetic acid has a second catalytic role through the formation of acetyl hypochlorite, which is much more reactive than HOCl in the transfer of Cl+ to ClO2- to form ClOClO.     

Syntheses, characterization, and magnetic studies of copper(II) complexes with the ligand N,N,N',N'-tetrakis(2-pyridylmethyl)-1,3-benzenediamine (1,3-tpbd) and its phenol derivative 2,6-bis[bis(2-pyridylmethyl)amino]-p-cresol] (2,6-Htpcd)

The copper(II) complexes [Cu(4)(1,3-tpbd)(2)(H(2)O)(4)(NO(3))(4)](n)(NO(3))(4n)·13nH(2)O (1), [Cu(4)(1,3-tpbd)(2)(AsO(4))(ClO(4))(3)(H(2)O)](ClO(4))(2)·2H(2)O·0.5CH(3)OH (2), [Cu(4)(1,3-tpbd)(2)(PO(4))(ClO(4))(3)(H(2)O)](ClO(4))(2)·2H(2)O·0.5CH(3)OH (3), [Cu(2)(1,3-tpbd){(PhO)(2)PO(2)}(2)](2)(ClO(4))(4) (4), and [Cu(2)(1,3-tpbd){(PhO)PO(3)}(2)(H(2)O)(0.69)(CH(3)CN)(0.31)](2)(BPh(4))(4)·Et(2)O·CH(3)CN (5) [1,3-tpbd = N,N,N',N'-tetrakis(2-pyridylmethyl)-1,3-benzenediamine, BPh(4)(-) = tetraphenylborate] were prepared and structurally characterized. Analyses of the magnetic data of 2, 3, 4, and [Cu(2)(2,6-tpcd)(H(2)O)Cl](ClO(4))(2) (6) [2,6-tpcd = 2,6-bis[bis(2-pyridylmethyl)amino]-p-cresolate] show the occurrence of weak antiferromagnetic interactions between the copper(II) ions, the bis-terdentate 1,3-tpbd/2,6-tpcd, μ(4)-XO(4) (X = As and P) μ(1,2)-OPO and μ-O(phenolate) appearing as poor mediators of exchange interactions in this series of compounds. Simple orbital symmetry considerations based on the structural knowledge account for the small magnitude of the magnetic couplings found in these copper(II) compounds.     

Tuning the photoinduced O2-evolving reactivity of Mn4O47+, Mn4O46+, and Mn4O3(OH)6+ manganese-oxo cubane complexes

The manganese-oxo "cubane" core complex Mn(4)O(4)L(1)(6) (1, L(1) = Ph(2)PO(2-)), a partial model of the photosynthetic water oxidation site, was shown previously to undergo photodissociation in the gas phase by releasing one phosphinate anion, an O(2) molecule, and the intact butterfly core cation (Mn(4)O(2)L(1)(5+)). Herein, we investigate the photochemistry and electronic structure of a series of manganese-oxo cubane complexes: [Mn(4)O(4)L(2)(6)] (2), 1(+)(ClO(4-)), 2(+)(ClO(4-)), and Mn(4)O(3)(OH)L(1)(6) (1H). We report the atomic structure of [Mn(4)O(4)L(2)(6)](ClO(4)), 2(+)(ClO(4-)) [L(2) = (4-MeOPh)(2)PO(2-)]. UV photoexcitation of a charge-transfer band dissociates one phosphinate, two core oxygen atoms, and the Mn(4)O(2)L(5)(+) butterfly as the dominant (or exclusive) photoreaction of all cubane derivatives in the gas phase, with relative yields: 1H > 2 > 1 > 2(+) > 1(+). The photodissociation yield increases upon (1) reducing the core oxidation state by hydrogenation of a corner oxo (1H), (2) increasing the electron donation from the phosphinate ligand (L(2)), and (3) reducing the net charge from +1 to 0. The experimental Mn-O bond lengths and Mn-O bond strengths and the calculated ligand binding energy explain these trends in terms of weaker binding of phosphinate L(2) versus L(1) by 14.7 kcal/mol and stronger Mn-(mu(3)-O)(core) bonds in the oxidized complexes 2(+) and 1(+) versus 2 and 1. The calculated electronic structure accounts for these trends in terms of the binding energy and antibonding Mn-O(core) and Mn-O'(ligand) character of the degenerate highest occupied molecular orbital (HOMO), including (1) energetic destabilization of the HOMO of 2 relative to 1 by 0.75 eV and (2) depopulation of the antibonding HOMO and increased ionic binding in 1(+) and 2(+) versus 1 and 2.