Thermochemical Study on [La(Hsal)2•(tch)]•2H2O [Hsal＝salicylate ( ), tch＝thioprolinate (C4H6NO2S-)]

The product from reaction of lanthanum chloride heptahydrate with salicylic acid and thioproline, [La(Hsal)2•(tch)]•2H2O, was synthesized and characterized by IR, elemental analysis, molar conductance, thermogravimatric analysis and chemistry analysis. The standard molar enthalpies of solution of LaCl3•7H2O (s), [2C7H6O3 (s)], C4H7NO2S (s) and [La(Hsal)2•(tch)]•2H2O (s) in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO) and 3 mol•L－1 HCl were determined by calorimetry to be [LaCl3•7H2O (s), 298.15 K]＝(－102.36±0.66) kJ•mol－1, [2C7H6O3 (s), 298.15 K]＝(26.65±0.22) kJ•mol－1, [C4H7NO2S (s), 298.15 K]＝(－21.79±0.35) kJ•mol－1 and {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}＝(－41.10±0.32) kJ•mol－1. The enthalpy change of the reaction LaCl3•7H2O (s)＋2C7H6O3 (s)＋C4H7NO2S (s)＝[La(Hsal)2•(tch)]•2H2O (s)＋3HCl (g)＋5H2O (l) (Eq. 1) was determined to be ＝(41.02±0.85) kJ•mol－1. From date in the literature, through Hess’ law, the standard molar enthalpy of formation of [La(Hsal)2•(tch)]•2H2O (s) was estimated to be {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}＝(－3017.0±3.7) kJ•mol－1.     

第35届国际化学奥林匹克理论试题答案

第一部分 :普通化学1　 (b)s =(Ksp/ 2 5 6 ) 1/ 52　 (b) [H+ ]=cHCl +Kw/ [H+ ]3　 (e) 10 0mL 0 .10M溶液含 18g葡萄糖4　 (b) (10 0 0×ρ×NA) /M5　 (a)K =Ksp(Ag2 CrO4 ) /Ksp(AgCl)26　 (c) 15 .0mL7　 (a)样品只含H3 PO4:曲线A(b)样品含H3 PO4和NaH2 PO4,摩尔比为 2∶1:曲线B(c)样品含H3 PO4和NaH2 PO4,摩尔比为 1∶1:曲线D8　 (b) 99　 (d) 2F10　(a) 683 0Zn +10n 6528Ni +Xα(b) 13 052Te +21H 13 153 I +Xn(c) 2 14 82Pb 2 14 83 Bi +X β(d) 2 3 11Na +10n 2 411Na +Xγ(e) 199F +10n 2 09F +Xγ11　 …     

氨·环己胺·羧酸根合铂(Ⅱ)类配合物的合成、抗肿瘤活性和与DNA的键合水平

本工作设计合成了6种新型氨·环己胺·羧酸根合铂!类配合物[Pt(NH3)(NH2)X2](a￣f)｛其中,X=CH3COO-(乙酸根),CH2ClCOO-(氯乙酸根),C6H5-COO-(苯甲酸根),p-CH3O-C6H4-COO-(对甲氧基苯甲酸根),p-CH3-C6H4-COO-(对甲基苯甲酸根),p-NO2-C6H4-COO-(对硝基苯甲酸根)｝。通过元素分析、摩尔电导、红外光谱、紫外光谱和1H核磁共振谱对配合物进行了表征。通过MTT法研究了配合物的体外抗肿瘤活性,通过流式细胞仪以及等离子体质谱研究了配合物对细胞周期的影响以及与细胞DNA的键合量;体外抗肿瘤活性测试表明,配合物(c￣f)对EJ和HL-602种肿瘤细胞表现出好的活性,而且配合物(c),(d)和(e)对EJ和HL-602种肿瘤细胞的活性高于临床用药顺铂;配合物(a￣f)对MCF-7、HCT-8和BGC-8233种肿瘤细胞的活性低于顺铂;它们能阻止HL-60和EJ细胞G2 M→G1期的进行;配合物(a￣f)与HL-60和EJ细胞的DNA键合量从大到小的顺序为:c>d>e>cisplatin>f>a>b。     

2006年全国高中学生化学竞赛理论试题参考答案

第1题1-1.A:Na2WO4;B:H2WO4或WO3·H2O;C:WO3⑴4FeWO4(s)+8NaOH(l)+O2(g)4Na2WO4(l)+2Fe2O3(s)+4H2O(g)2MnWO4(s)+4NaOH(l)+O2(g)2Na2WO4(l)+2MnO2(s)+2H2O(g)(产物写成Mn2O3或Mn3O4也可)⑵Na2WO4(aq)+2HCl(aq)H2WO4(s)+2NaCl(aq)⑶H2WO4(s)WO3(s)+H2O(g)1-2.[1]2WO3(s)+3C(石墨)2W(s)+3CO2(g)[2]反应在298.15K时的标准焓变、标准熵变和标准自由能变化分别为:ΔH=ΣυΔfH m=[2×0+3×(-393.51)-2×(-842.87)-3×0]kJ/mol=505.21 kJ/molΔS=ΣυS=[2×32.64+3×213.64-2×75.90-3×5.74]J·mol-1·K-1=537.…     

丙烯醛亚硫酸氢钠加合物的晶体结构

丙烯醛亚硫酸氢钠加合物,(CH_2=CH-CHO·2NaHSO_3·4H_2O)的空间群为 D_(2h)~(13) -P2_1/m 2_1/m 2/n,每个晶胞中含有2个克式量的加合物,正交晶胞的参数为 a=18. 24,b=7. 05,c=4. 77。从 Patterson 函数 P u,0,w),P(u,1/4,w)和 P(u,0. 35,w)中引出 SO_3 团和钠原子的参数。从上述参数合成了 Fourier 投影ρ(x,y)和 P(x,z),得出整个结构的模型和参数。根据这些参数合成的 Fourier 切面ρ(x,1/4,z)进一步确定了上述结构模型。上述结构分析的结果指出:(1) 丙烯醛加合物是1-羟基丙烷-1,3-二磺酸的钠盐,Na_2[O_3SCHOHCH_2CH_2SO_3] ·4H_2O;(2) 二磺酸根离子中的 C-S=1. 78(平均长度),S-O=1. 42(平均长度),其余的数据和一般共价单键者很接近;(3) 钠离子处在磺酸根和水分子的氧原子形成的八面体配位中;(4) 水分子以氢键填充在分布於和(010) 平行的层中的二磺酸根离子间的空隙中,而钠离子通过它的氧原子配位使各二磺酸根离子层连接起东;(5) 在每个二磺酸根离子中,羟基可以机遇地分布在四个等同的 a 位置上:(6) 晶体含有同数的1-羟基丙烷-1,3-二磺酸根离子的对映体;(7) 晶体中的水分子亦参与使晶体取得 D_(2h)对称性的无序现象。本工作使醛的亚硫酸氢盐加合物是 a 羟基磺酸盐的观点取得了新的、富有说服力的论证。     

扑疟喹啉用作无机分析试剂Ⅰ.——铬(Ⅵ)的检验

(1)扑疟喹啉在0.1N高氯酸和8％草酸的条件下与铬酸根作用显紫色。检出限为0.05γ,界限稀度为1:10~6。Ce~(+4),Au~(+3),VO_3~-,BrO_3~-,IO_3~-,IO_4~-和NO_2~-有干扰作用。 (2)已测定铬酸根与七十四种离子界限比率。大部分以1:200的界限比率对检出的灵敏度无影响。     

中国科学院上海有机化学研究所 1988年研究生入学考试试题及参考答案

物理化学答案一1.(e);2。(a,d);3.(e、;4。(遵), 汤.(b);(,。(a);7.(b);8.咬c),9.(a); 1 0.(b)二.1.△HO:9。二(八“。r,HZ) (△月o,,伪2)一(AHOr,.:o 卜乙衬0丁,)1-120(g)=一393.51 110.52 241‘83 =一选1。16 kJ 乙C,二(29.07十26。00一26.86一30.36) (一0 .836一卜理3。5一6.97一9.61)x1O3T =一2 .15 26。08又10一3T““7。。=“HOZOS「{{::八C·dT二一36·7”k,△G02;。=△GDf,HZo(:)一△G们,,InZo川=一228.59 237.19二8.60kJ p二e一△。0,斤了=0 .03108(atm) 二23.6(mmHg)(25℃水的饱和蒸汽压)3.Ag:o的分解反应 AgZo(s)…     

STUDIES ON RARE EARTH METAL COMPLEXES OF AMINO ACIDS. THE SYNTHESIS AND CRYSTAL STRUCTURE OF TE-TRAKIS ( ALANINE ) OCTAAQUODILANTHANIDE HEXAPER-CHLORATE [Ln_2(Ala)_4(H_2O)_8]*(ClO_4)_6(Ln = Er~(3+)and Eu~(3+),Ala=CH_3CH(~+NH_3)COO~-)

<正> Complex [Er2(Ala)4(H2O)8]·(ClO4)6, 1, Mr = 1431. 8, mono-clinic, space group C2/c with cell parameters a= 18. 21(1), 6 = 14. 67(2), c=17. 19(3)(?), β=101. 60(8)°, V = 4495(4)(?)3, Dc=2.11g/cm3, Do = 2. 09g/cm3, Z = 4, F (000) = 2808, μ= 42. 30cm-1; Complex [Eu2(Ala)4(H2O)8]·(ClO4)6, 2, Mr = 1401.4, monoclinic, space group C2/c, a = 18. 16(4) , b = 14.52(2), c=17. 35(1)(?), β=102. 3(1)°, Z = 4, V= 4468(11)(?)3. The structure of complex 1 is refined by full-matrix least - squares method with 3348 observed reflections (I≥3σ (I)) to R = 0. 048 and Rw= 0.060. The two erbium ions in the dimeric complex cation [Er2(Ala)4(H2O)8]]6+ are connected by four bridging carboxylato groups, each pair of the carboxylato groups is coplanar with the two Er(III) ions and the dihedral angle between the two planes is 91. 42*. Each Er3+ion is coordinated by four carboxylato oxygen atoms and four water oxygen atoms, assuming a square antiprism arrangment. The alanine exists in the form of CH3CH (+NH3) COO- , and the mo     

á-(BEDT-TTF)_2C_6H_4(SO_3)_2的合成、结构与导电性

用恒电流电化学结晶法合成了一种新的基于BEDT TTF的电荷转移盐α′ (BEDT TTF) 2 C6H4 (SO3 ) 2 [BEDT TTF =双亚乙基二硫四硫富瓦烯 ,C6H4 (SO3 ) 2 -2 =对苯二磺酸根 ].通过四圆X射线衍射方法测定了α′ (BEDT TTF) 2 C6H4 (SO3 ) 2 的结构 .晶体属于单斜晶系 ,P2 /n空间群 ;晶胞参数 :a =0 .77937(17)nm ,b =0 .6 6 989(11)nm ,c =3.44 2 2(7)nm ,β =91.135 (12 )°,V =1.796 8(6 )nm3 .该晶体中BEDT TTF+ 自由基沿a轴方向形成具有二聚体结构的交错排列型柱状堆积 ,沿b轴方向由肩并肩强分子间相互作用形成一维分子链 .电荷补偿阴离子C6H4 (SO3 ) 2 -2 则在a方向存在较强的作用 .沿c轴方向 ,BEDT TTF+ 自由基层和阴离子层交替排列形成夹心式结构 .α′ (BEDT TTF) 2 C6H4 (SO3 ) 2 在ab面的某方向的室温电导率为 0 .5 913Ω-1·m-1,电阻率 -温度测定曲线表明它具有半导体导电行为 .在15 0K附近 ,晶体发生了某种相变     

Studies on the Synthesis of Preverecynarmin

Prev~n1,acembranopditerpenoid,wasfirstisolatedfromsoftcoral(VeretilIumcoporium)inl99(),anditSmCtUrwasehablishedas(+)-(lE,3E,7E,llE)-cembra-l,3,7,ll-tetraen6-olaeetate[l].SofarasweknOW,thetotalSynthsisof1hasnobeenrePOrtedyet.Herein.wewishtodescribethetotalpeisoftheprecursor(9),theSynthhcroutewasouthnedbelowfa)HBr.80%;b).CH3C02Na.CH3CO2H,75%,c).Se02-I-Bu00H,70%,d).CCl',PPh3,83%,e).NaSQPh.DMF.9O%,O.K=CO3.MeOH,95%,g).DHP,Ts0H.8O%,h),TBAB,5O%NaOH,aq.,5%;i).Li-Effez.M,70%;j…     

CRYSTAL STRUCTURE OF [Ni((C)_6H_(11)O)_2PS_2)·(C_4H_9NH_2)_4]-(C_6H_(11)O)_2PS_2

<正> [Ni((C6H11O)2PS2)·(C4H9NH2)4](C6H11O)2PS2,Mr-=938. 05, triclinic,P1,a=13. 513(6),b=16. 040 (7), c= 12. 891(6) A , α= 95. 66 (4),β= 90. 23(4),γ= 75. 46(3)°,V = 2691 A3,Z=2,Dc= 1. 16 g·cm3.μ=6. 07cm-1,MoKa radiation, λ=0. 71069 A ,F(000) = 1020,R=0. 100 for 4595 reflections with I≥3σ(I). The title compound molecule consists of a complex cation [Ni((C6H11O)2PS2)(C4H9-NH2)4]+ and a complex anion (C6H11O)2PS2- . The Ni (Ⅱ) atom in the cation is octahedrally coordinated by four nitrogen atoms from four w-butylamine ligands and two sulfur atoms from one (C6H11O)2PS2 group.     

Anionic polymerization of fluorine-substituted phenyl methacrylates

Synthesis and anionic polymerization of the fluorine-substituted phenyl methacrylates are herein reported.A series of mono-,di-,and multi-substituted fluorophenyl methacrylates H2C=C(CH3)C(O)OC6H4F-4(M1a),H2C=C(CH3)C(O)OC6H4F-3(M1b),H2C=C(CH3)C(O)OC6H3F2-2,4(M2),H2C=C(CH3)C(O)OC6H2F3-2,3,4(M3),H2C=C(CH3)C(O)OC6HF4-2,3,5,6(M4),and H2C=C(CH3)C(O)OC6F5(M5)were synthesized and characterized.Initially,the polymerization was carried out on the monomer M1a by using n Bu Li,t Bu Li,and KH as the respective catalysts;this approach produced the polymers in yields of12%–50%,but with lower molecular weights.Similar results were obtained by using t Bu Li for catalytically polymerizing the other five monomers.By introducing a co-catalyst Me Al(BHT)2,the catalysts Na H,Li H,and t Bu OLi each were tested to polymerize M1a,which gave the polymers in very low yields(3%–7%).Polymer yields of 13%–27%were obtained by each of the catalysts Li Al H4,n Bu Li,Ph Li,and t Bu Li in connection with Me Al(BHT)2,but a better yield(61%)was achieved with KH/Me Al(BHT)2.The KH/Me Al(BHT)2 catalyst system was further employed to polymerize M1b and M2,which afforded respective polymer yields of 12%–63%and 10%–53%,depending on the molar ratios of KH:Me Al(BHT)2 as well as on the monomer concentrations.All of the polymers produced were syndiotactically rich in structure,as indicated by either 1H or 19F NMR data.The polymerization mechanism by the combined catalyst system is proposed.     

钛,锆和铪羰基化合物M(CO)_n(M=Ti,Zr,Hf;n=4～7)的理论研究

利用密度泛函方法对标题化合物的平衡几何、热化学及振动频率进行了理论预测,发现这3种金属原子都有相似的M(CO)n(n=4～7)结构.全局最低构型对M(CO)7都是单态C3v戴帽八面体7S-1,对M(CO)6都是三重态D3d畸变八面体6T(而对应的单重态M(CO)5仅比它低不到21 kJ·mol-1).对M(CO)n(n=5,4)都是三重态6S-1,其构型分别为从6T中移去1个或2个CO基的衍生物5T和4T.此外,五重态的D3h的三角双锥M(CO)5和单态的Td四面体M(CO)4以及能量更高的含有C和O同时与金属成键的独特配位CO基的M(CO)6和M(CO)3也被发现.最后,给出M(CO)7→M(CO)6+CO反应的离解能.并讨论了金属18价电子的Ti(CO)7存在的可能性.     

Highly efficient nickel/phosphine catalyzed cross-couplings of diarylborinic acids with aryl tosylates and sulfamates

<正>4-Methoxy-4′-methylbiphenyl(3aa) [1] MeO White solid(0.324 g, 82% from aryl tosylate, 0.356 g, 90% from aryl sulfamate); m.p. 111–112 °C; 1H NMR(400 MHz,CDCl3) δ 7.50(d, J = 8.4 Hz, 2H), 7.44(d, J = 8.0 Hz, 2H), 7.21(d, J = 8.0 Hz, 2H), 6.95(d, J = 8.8 Hz, 2H), 3.82(s, 3H), 2.37(s, 3H); 13 C NMR(100 MHz, CDCl3) δ 159.0, 138.0, 136.4, 133.8, 129.5, 128.0, 126.6, 114.2, 55.4, 21.1. 4,4′-Dimethylbiphenyl(3ab) [1] White solid(0.320 g, 88% from aryl tosylate, 0.346 g, 95% from aryl sulfamate); m.p. 122–123 °C; 1H NMR(400 MHz,CDCl3) δ 7.47(d, J = 8.0 Hz, 4H), 7.22(d, J = 8.0 Hz, 4H), 2.37(s, 6H); 13 C NMR(100 MHz, CDCl3) δ 138.4, 136.8, 129.5, 126.9, 21.2.     

苯并18-冠-6与M_2[Pt(SCN)_6](M=Na,K)配合物的合成、结构

合成了苯并 18 冠 6(B18C6)与M2 [Pt(SCN)6 ](M =Na,K)的配合物:｛[Na(B18C6)]6 [Pt(SCN)6 ]｝[Pt(SCN)6 ](SCN)2(1),[K(B18C6)]2 [Pt(SCN)6 ]·4H2 O(2).通过元素分析、红外光谱、单晶X射线衍射进行了表征.1为单斜晶系、空间群R3- ,a =b =1 9933(3)nm,c =2 9760 (6)nm,α =β =90°,γ =12 0°,V =10 2 40 (3)nm3,Z =3,Dcalcd=1 5 64g/cm3,F(0 0 0) =490 8,R1=0 0 5 35,wR2 =0 10 30.2为三斜晶系、空间群P1- ,a =1 1692 (3)nm,b =1 185 3(4)nm,c =1 2 381(5)nm,α =61 419(5)°,β =80 75 7(8)°,γ =89 0 0 3(5)°,V =1 4836(9)nm3,Z =1,Dcalcd=1 476g/cm3,F(0 0 0) =666,R1=0 0 696,wR2 =0 134 6. 1由 ｛[Na(B18C6)]6 [Pt(SCN)6 ]｝4 +配阳离子、[Pt(SCN)6 ]2 -配阴离子和SCN-阴离子组成.相邻｛[Na(B18C6)]6 [Pt(SCN)6 ]｝4 +通过Na—O键形成三维网状结构.[Pt(SCN)6 ]2 -和SCN-仅起平衡电荷的作用.2由两个[K(B18C6)]+配阳离子和一个[Pt(SCN)6 ]2 -配阴离子组成.相邻[K(B18C6)]2 [Pt(SCN)6 ]离子对通过K—O键形成一维链状结构     

Degradation Method for Preparing Organo-Arsenic and-Antimony Polytungstates and Comparative Study of Corresponding Polymolybdates

In repeating and extending the syntheses of organo-arsenic polytungstates,we found that the "Degradation Method",taking sodium metatungstate as the starting material,was much more profita-ble.The known compound (CN3H6)5[(C6H5As)2W6O25H]2H2O(1) was read-ily reproduced with a high yield.A new compound (CN3H6)6[(p-OH,m-NO2C6H3As)2W6O25](2) was likewise synthesized.This "Degradation Method" using the reaction of sodium metatungstate with organo-anti-monate led to the isolation of four compounds with definite composition although amorphous in appearance.The preparations of organo-arsenic polymolybdates and organo-antimony polymolybdates were also studied and six new organo-arsenic polymolybdates were isolated: (CN3H6)5[(C6H5As)2MoO25H]H2O(3),(CN3H6)4[(n-C3H7As)2Mo5O21]2H O (4),(CNH)4[(n-C3H7As)2Mo6O24](5),Cs2[(CH3)2AsMo4O15H](6),相似文献   

CRYSTAL AND MOLECULAR STRUCTURE OF TRIS (HYDROX-YMETHYL) AMINOM ETHANE ARSENATE (THAMAS)

<正> (CH2OH)3CNH3H2AsO4, M, = 263. 08, monoclinic, space group P21, with a = 8. 232(2), b = 6. 180(2), c=9. 856(3)(?) , β=104. 77(2)°, Z = 2, V = 484. 81(?)3, Dc= 1. 80 g/cm3, MoKα radiation, μ = 35. 02cm-1, F(000) = 268. The final R and Rw are 0. 040 and 0. 037, respectively. The molecule of THAMAS is composed of TAMH+ and H2AsO4- which are held together by a hydrogen bond. Adjacent molecules in THAMAS crystals are connected by intermolecular hydrogen bonds.     

中国科学院上海有机学化学研究所1982年研究生入学试题参考答案

无机及分析化学.KZCr:0,+6FeSO。+7HZSO。(稀)一一)Cr:(50一)s+3 Fe:(50一)3+KZSO一+7 HZO2 .2 KM几0一+3 Na:503+HZO~-今 e H H什处 H ZMnO:杏+3NaZSO。+ZKOH __乙 3 .FeC:O‘二)FeO+CO+CO: 4 .ZNaNOZ+ZNal+ZHZSO---) 2 NO个+I:+2 Na:50‘+2 HZO 5 .Aszsa+6 NaOH-se-) Na:Asoa+Na3AsS,+3H:O 1.在pH;7~8时: 10不+HZO+21一不2 2 OH一+10三+I: 2.在PH一1时: 10不+SH十+71一不全4HZO+41:三、上述四种性质中只有原子摩尔体积、第一电离势、电负性具有周期性。 1.原子摩尔体积:一个周期中二端的元素具有较…     

新型三元配合物[RE(C_7H_5O_3)_2(C_6H_4NO_2)·H_2O](RE=La,Ce,Nd)的合成、光谱特性和热化学性质

采用均匀沉淀法,在20%的乙醇水溶液中,用水杨酸、维生素B3与稀土硝酸盐合成了一类新的稀土三元配合物.通过元素分析、化学分析、摩尔电导、红外光谱、紫外光谱、热重-微分热重分析等手段对配合物的结构和性质进行表征,确定了它们的组成通式为[RE(C7H5O3)2(C6H4NO2)·H2O](RE=La,Ce,Nd).维生素B3吡啶环上的N原子和水杨酸的酚羟基均未参与配位,两种配体均是脱质子后以羧酸根与RE3+离子配位,且成键以离子性为主,兼有部分共价性.在298.15 K,用精密的溶解-反应热量计分别测量了配位反应相关各物质的溶解焓,根据盖斯(Hess)定律求得合成反应的标准摩尔反应焓r mHФ分别为:(180.61±0.72)、(187.25±0.68)和(185.61±0.26)kJ/mol.进而求出配合物的标准摩尔生成焓为:f mHФ[La(C7H5O3)2(C6H4NO2)·H2O(s),298.15 K]=-(2493.9±2.9)、f mHФ[Ce(C7H5O3)2(C6H4NO2)·H2O(s),298.15 K]=-(2441.0±2.8)和f mHФ[Nd(C7H5O3)2(C6H4NO2)·H2O(s),298.15 K]=-(2463.1±2.9)kJ/mol.     

The preparation, structure and spectra properties of dual μ3-oxo bridged tetranuclear complexes containing the [CrnFe4-nO2]8+ core(n=0,2,4)

The preparation and characterization of [CrnFe4-nO2(O2CMe)7(bipy)2]Cl (1, n=0; 2, n=2; 3, n=4, bipy=2,2'-bipyridine) are described. The three complexes (1, 2 and 3) are obtained by tipyridine-mediated conversion of trinuclear [CrnFe3-nO(O2CMe)6(H2O)3]+(1, n=0; 2, n=1;3, n=3), and crystallized as three of approximate isomorphs. Crystal 2 is monoclinic with space group C2/c, a=27.454(5)A, b=11.789(1)A, c=16.570(3)A, B=118.78(1), V=4700.8A, z=4, u(MoKa)=11.64cm-1, F(000)=2056, final R=0.058 and Rw=0.066 for 3479 reflections with I > 3o(I). The Fe and Cr atoms in the cation are all +3 oxide state and disordered in the lattice, which is also supported by its Mossbauer studies. The [Cr2Fe2O2]8+ core can be thought of as being derived from two edge-sharing M3O units (M=Fe or Cr), and as a butterfly-like structure. The cations' structure of all three crystals are similar to each other and have C2 symmetry. The species are characterized by IR spectra and magnetic techniques, with particular emphasis on different