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1.
A high‐pressure phase of magnesium chloride hexahydrate (MgCl2·6H2O‐II) and its deuterated counterpart (MgCl2·6D2O‐II) have been identified for the first time by insitu single‐crystal X‐ray and powder neutron diffraction. The crystal structure was analyzed by the Rietveld method for the neutron diffraction pattern based on the initial structure determined by single‐crystal X‐ray diffraction. This high‐pressure phase has a similar framework to that in the known ambient‐pressure phase, but exhibits some structural changes with symmetry reduction caused by a subtle modification in the hydrogen‐bond network around the Mg(H2O)6 octahedra. These structural features reflect the strain in the high‐pressure phases of MgCl2 hydrates.  相似文献   

2.
The new complex, cis‐β‐[Cr(2,2,3‐tet)(N3)2]Br (2,2,3‐tet = 1,4,7,11‐tetraazaundecane), was prepared and its structure was determined by single‐crystal X‐ray diffraction. The chromium(III) atom is in a distorted octahedral environment coordinated by four nitrogen atoms of 2,2,3‐tet and two azido ligands in a cis‐β arrangement, with bent Cr–N3 linkages at the coordinating azide nitrogen atoms. The mean Cr–N(2,2,3‐tet) and Cr–N(azide) bond lengths are 2.084(5) and 2.021(5) Å, respectively. The crystal structure is stabilized by ionic interactions, supported by N–H ··· N(azide) and N–H ··· Br hydrogen bonds. The IR and electronic spectroscopic properties are also discussed.  相似文献   

3.
Polysulfonylamines. CLXXXIV. Crystal Structures of Molecular Triphenylphosphanegold(I) Di(4‐X‐benzenesulfonyl)amides: Isomorphism and Close Packing (X = Me, F, Cl, NO2) vs. Structure‐Determining C–X···Au/O Halogen Bonds (X = Br, I) In order to study the structure‐determining influence that halogen bonding can exert during the course of crystallization, solid‐state structures are compared for two previously reported and four new molecular gold(I) complexes of the type Ph3P–Au–N(SO2–C6H4–4‐X)2, each featuring linear P,N coordination at gold and two phenyl rings with varying p‐substituents X = Me, F, Cl, NO2, Br or I. The compounds were synthesized by reactions of Ph3PAuX (X = Cl or I) with the corresponding silver di(arenesulfonyl)amides, crystallized from dichloromethane, and characterized by low‐temperature X‐ray diffraction. The Me, F, Cl and NO2 congeners are isomorphic and crystallize without solvent inclusion in the chiral orthorhombic space group P212121 (Z′ = 1). These structures are governed by isotropic close packing via three‐dimensional 21 symmetry, incidentally supported by an invariant set of C–H···O=S hydrogen bonds, CH/π interactions and π/π stackings of aromatic rings; in particular, the hard halogen atoms of the fluoro and the chloro homologues are not involved in X···Au, X···O or X···X interactions. The higher homologues, with soft halogen atoms, were obtained as a dichloromethane hemisolvate for X = Br and a corresponding monosolvate for X = I, each triclinic in the centrosymmetric space group (Z′ = 1). Here, the primary structural effect is implemented by infinite chains in which translation‐related molecules are connected for the bromo compound by a bifurcated Au···Br(2)···O=S interaction, for the iodo congener by an equivalent Au···I(2)···O=S interaction and a short halogen bond C–I(1)···O=S. The latter bond is stronger than a similar C–Br···O=S interaction and induces a conformational adjustment of the (CSO2)2N group from the normal twofold symmetry in the bromo compound to an energetically unfavourable asymmetric form in the iodo homologue. In both cases, pairs of antiparallel molecular catemers are associated into strands via sixfold phenyl embraces, the strands are stacked to form layers, the solvent molecules are intercalated between adjacent layers, and the crystal packings are reinforced by a number of C–H···O=S hydrogen bonds and interactions of aromatic rings.  相似文献   

4.
Three new coordination compounds, [Pb(HBDC‐I4)2(DMF)4]( 1 ) and [M(BDC‐I4)(MeOH)2(DMF)2]n (M = ZnII for 2 and MnII for ( 3 ) (H2BDC‐I4 = 2, 3, 5, 6‐tetraiodo‐1, 4‐benzenedicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X‐ray single crystal structure analysis. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic space group C2/c and has a discrete mononuclear structure, which is further assembled to form a two‐dimensional (2D) layer through intermolecular O–H ··· O and C–H ··· O hydrogen bonding interactions. The isostructural compounds 2 and 3 crystallize in the space group P21/c and have similar one‐dimensional (1D) chain structures that are extended into three‐dimensional (3D) supramolecular networks by interchain C–H ··· π interactions. The PbII and ZnII complexes 1 and 2 display similar emissions at 472 nm in the solid state, which essentially are intraligand transitions.  相似文献   

5.
Three new complexes: [M(L)(H2O)] [M = Zn ( 1 ), Co ( 2 ), Ni ( 3 ); H2L = 5‐(pyridin‐2‐ylmethyl)aminoisophthalic acid] were synthesized under hydrothermal conditions at 180 °C and were characterized by elemental analysis, FT‐IR spectroscopy, single‐crystal X‐ray diffraction, and thermogravimetric analysis (TGA). The results of X‐ray diffraction analysis reveal that complexes 1 – 3 are isostructural and crystallize in the monoclinic system with space group P21/c. Each of the complexes displays a (3,3′)‐connected two‐dimensional (2D) wave‐like network with (4,82) topology, within which five‐membered uncoplanar N,N‐chelated metallacycles are shaped. Delicate N–H ··· O and O–H ··· O hydrogen bonding interactions exist in complexes 1 – 3 . Adjacent 2D layers are linked by intermolecular interactions, resulting in the construction of extended metal‐organic frameworks (MOFs) in complexes 1 and 2 .  相似文献   

6.
A ZnII compound based on the semi‐rigid dipolar ligand 1,4‐bis(benzimidazol‐1‐ylmethyl)benzene (L), {[Zn( L )2Cl2]·2DMF}n ( 1 ) has been synthesized successfully under solvothermal conditions. X‐ray single crystal diffraction shows that the complex contains P‐helical and M‐helical chains with 21 screw axis but crystallizes as a racemate. Through π···π stacking interactions between two well‐overlapping benzimidazoleyl rings from two adjacent chains, the 3D racemic supramolecular network is assembled. Furthermore, the IR, TGA and luminescent properties are also investigated in this work.  相似文献   

7.
The title compound, rac‐6,13‐dihydro‐6,13‐methanopentacene ( 1 ), has been synthesized and characterized by elemental analysis, FT‐IR, 1H NMR, UV‐Vis, HRMS spectra, cyclic voltammetry and single‐crystal X‐ray diffraction. The crystal belongs to orthorhombic, space group P212121, with Z = 4 and cell dimensions a = 6.0185(4), b = 8.1914(6), c = 31.4080(19) Å. In the crystal structure, two types of intermolecular C–H···π hydrogen bonds are observed, and further stabilize the crystal structure. Its photophysical and electrochemical properties and complementary density functional theory (DFT) calculations are reported.  相似文献   

8.
Two kinds of iodine–iodine halogen bonds are the focus of our attention in the crystal structure of the title salt, C12H8ClINO+·I3, described by X‐ray diffraction. The first kind is a halogen bond, reinforced by charges, between the I atom of the heterocyclic cation and the triiodide anion. The second kind is the rare case of a halogen bond between the terminal atoms of neighbouring triiodide anions. The influence of relatively weakly bound iodine inside an asymmetric triiodide anion on the thermal and Raman spectroscopic properties has been demonstrated.  相似文献   

9.
The adsorption behaviour of the CdII–MOF {[Cd(L)2(ClO4)2]·H2O ( 1 ), where L is 4‐amino‐3,5‐bis[3‐(pyridin‐4‐yl)phenyl]‐1,2,4‐triazole, for butan‐2‐one was investigated in a single‐crystal‐to‐single‐crystal (SCSC) fashion. A new host–guest system that encapsulated butan‐2‐one molecules, namely poly[[bis{μ3‐4‐amino‐3,5‐bis[3‐(pyridin‐4‐yl)phenyl]‐1,2,4‐triazole}cadmium(II)] bis(perchlorate) butanone sesquisolvate], {[Cd(C24H18N6)2](ClO4)2·1.5C4H8O}n, denoted C4H8O@Cd‐MOF ( 2 ), was obtained via an SCSC transformation. MOF 2 crystallizes in the tetragonal space group P43212. The specific binding sites for butan‐2‐one in the host were determined by single‐crystal X‐ray diffraction studies. N—H…O and C—H…O hydrogen‐bonding interactions and C—H…π interactions between the framework, ClO4? anions and guest molecules co‐operatively bind 1.5 butan‐2‐one molecules within the channels. The adsorption behaviour was further evidenced by 1H NMR, IR, TGA and powder X‐ray diffraction experiments, which are consistent with the single‐crystal X‐ray analysis. A 1H NMR experiment demonstrates that the supramolecular interactions between the framework, ClO4? anions and guest molecules in MOF 2 lead to a high butan‐2‐one uptake in the channel.  相似文献   

10.
The zinc(II) coordination polymers [Zn(Htatb)(2,2′‐bipy) · (NMP) · H2O] ( 1 ) and [Zn3(tatb)2(2,2′‐bipy)3 · H2O] ( 2 ) (H3tatb = 4,4′,4′′‐s‐triazine‐2,4,6‐triyl‐tribenzoic acid; 2,2′‐bipy = 2,2′‐bipyridyl, NMP = N‐methyl‐2‐pyrrolidon), were synthesized hydrothermally, and characterized by infrared spectroscopy (IR), powder X‐ray diffraction (PXRD), and single‐crystal X‐ray diffraction. Both compounds 1 and 2 possess expectant low dimensional coordination structures, which further connected into interesting 3D networks by hydrogen bond and strong π–π interactions. Moreover, the thermal stabilities and fluorescent properties of 1 and 2 were investigated.  相似文献   

11.
Chemistry of Polyfunctional Molecules. 133. X‐Ray Crystal Structural, Solid‐state 31P CP/MAS NMR, TOSS, 31P COSY NMR, and Mechanistic Contributions to the Co‐ordination Chemistry of Octacarbonyldicobalt with the Ligands Bis(diphenylphosphanyl)amine, Bis(diphenylphosphanyl)methane, and 1,1,1‐Tris(diphenylphosphanyl)ethane Co2(CO)8 reacts with bis(diphenylphosphanyl)amine, HN(PPh2)2 (Hdppa, 1 ), in two steps to afford the known compound [Co(CO)(Hdppa‐κ2P)2][Co(CO)4] · 2 THF ( 6 a · 2 THF). The intermediate [Co(CO)2(Hdppa‐κ2P) · (Hdppa‐κP)][Co(CO)4] · dioxane · n‐pentane ( 5 · dioxane · n‐pentane) was isolated for the first time and was characterized by X‐ray analysis. The cation 5 + exhibits a slightly distorted trigonal‐bipyramidal geometry. Detailed 31P‐NMR investigations (solid‐state CP/MAS NMR, TOSS, 31P‐COSY, 31P‐EXSY) showed that the additional tautomer [Co(CO)2(Hdppa‐κ2P)(Ph2P–N=P(H)Ph2‐κP)]+ ( 5 ′+) is present in solution. The tautomer equilibrium is slow in the NMR time scale. In contrast to the solid state only tetragonal pyramidal species of 5 are found in solution. At –90 °C there is slow exchange between the three diastereomeric species 5 a +– 5 c +. Compound 5 forms [Co(CO) · (Hdppa‐κ2P)2]BPh4 · THF ( 6 b · THF) in THF with NaBPh4 under CO‐Elimination. A X‐ray diffraction investigation shows that the cation 6 + consists of a slightly distorted trigonal‐bipyramidal co‐ordination polyeder. However, a distorted tetragonal‐pyramidal structure has been found for the cation 7 + of the related compound [Co(CO)(dppm)2][Co(CO)4] · 2 THF ( 7 · 2 THF; dppm = bis(diphenylphosphanyl)methane, Ph2PCH2PPh2). A comparison with the known [8] trigonal‐bipyramidal stereoisomer, ascertained for 7 + of the solvent‐free 7 , is described. In solutions of 6 a · 2 THF and 7 · 2 THF 13C{1H}‐ and 31P{1H}‐NMR spectra indicate an exchange of all CO and organophosphane molecules between cobalt(I) cation and cobalt(–I) anion. A concerted mechanism for the exchange process is discussed. CO elimination leads to discontinuance of the cyclic mechanism by forming binuclear substitution products such as the isolated Co2(CO)2 · (μ‐CO)2(μ‐dppm)2 · 0.83 THF ( 8 · 0.83 THF), which was characterized by spectroscopy and X‐ray analysis. For the dissolved [Co(CO)2CH3C(CH2PPh2)3][Co(CO)4] · 0.83 n‐pentane ( 9 a · 0.83 n‐pentane) no CO and triphos exchange processes between the cation and the anion are observed. Metathesis of 9 a · 0.83 n‐pentane with NaBPh4 yields [Co(CO)2CH3C(CH2PPh2)3]BPh4 ( 9 b ) which has been characterized by single‐crystal X‐ray analysis. The cation shows a small distorted tetragonal‐pyramidal structure.  相似文献   

12.
The Co‐MOF poly[[diaqua{μ4‐1,1,2,2‐tetrakis[4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl]ethylene‐κ4N:N′:N′′:N′′′}cobalt(II)] benzene‐1,4‐dicarboxylic acid benzene‐1,4‐dicarboxylate], {[Co(C34H24N12)(H2O)2](C8H4O4)·C8H6O4}n or {[Co(ttpe)(H2O)2](bdc)·(1,4‐H2bdc)}n, (I), was synthesized by the hydrothermal method using 1,1,2,2‐tetrakis[4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl]ethylene (ttpe), benzene‐1,4‐dicarboxylic acid (1,4‐H2bdc) and Co(NO3)2·6H2O, and characterized by single‐crystal X‐ray diffraction, IR spectroscopy, powder X‐ray diffraction (PXRD), luminescence, optical band gap and valence band X‐ray photoelectron spectroscopy (VB XPS). Co‐MOF (I) shows a (4,4)‐connected binodal two‐dimensional topology with a point symbol of {44·62}{44·62}. The two‐dimensional networks capture free neutral 1,4‐H2bdc molecules and bdc2? anions, and construct a three‐dimensional supramolecular architecture via hydrogen‐bond interactions. MOF (I) is a good photocatalyst for the degradation of methylene blue and rhodamine B under visible‐light irradiation and can be reused at least five times.  相似文献   

13.
A new mixed ligand palladium(II) complex with bidentate NS‐donor chelate, [PdCl(PPh3)L] (L: S‐allyl βN‐(benzylidene)dithiocarbazate), has been prepared and characterized using single crystal X‐ray diffraction and spectroscopic (electronic, IR, 1H NMR and 13C NMR) techniques. The shorter Pd? P bond distance, 2.255(7) Å, than the sum of the single bond radii for palladium and phosphorus (2.41 Å), showed partial double bond character. Visualizing and exploring the crystal structure using Hirshfeld surface analysis showed the presence of π··· π, N··· π, C? H··· π, Cl···H and weak C? H···S interactions as most important intermolecular interactions in the crystal lattice, which are responsible to extension of the supramolecular network of the compound and stabilization of the crystal structure.  相似文献   

14.
A mononuclear Cu(II) complex with mixed ligands, formulated as [Cu(hypydc)(dmp)]·H2O (hypydc=4‐hydroxypyridine‐2,6‐dicarboxylate, dmp=2,9‐dimethyl‐1,10‐phenanthroline), was synthesized and well characterized by single crystal X‐ray diffraction analysis, as well as spectroscopic (IR, UV‐Vis), and electrochemical methods. The Cu(II) atom exhibits a distorted square‐pyramidal geometry. Intermolecular O? H···O and C? H···O hydrogen bonds, π‐π stacking interactions and C? H···π interactions seem to be effective in the stabilization of the crystal structure. The complex was also evaluated for its antimicrobial activity using in vitro microdilution methods. Six standard bacteria and a strain of Candida albicans were used for the antimicrobial activities. There was a very strong activity against Candida albicans and significant activities against Enterococcus fecalis, Listeria monocytogenes, Bacillus cereus and Staphylococcus aureus, indicating important biological activities of the complex.  相似文献   

15.
Crystals of the 4‐halo‐1,2,3,5‐dithiadiazolyl radicals (X = F, Cl, Br) were obtained by sublimation at 80 °C and 10?2 Torr, and the structures were determined by X‐ray diffraction. The fluoro derivative crystallizes as a cisoid dimer in the space group P21/n, whereas the chloro and bromo derivatives crystallize isomorphous as twisted dimers in the space group C2/c. The chloro and bromo derivatives show the shortest intradimer S···S contacts of all known 1,2,3,5‐dithiadiazolyl dimers. In addition the obtained structure of ClCN2S2? represents the fifth polymorph of ClCN2S2? characterized by X‐ray crystallography. The structures and the packing including secondary interactions are discussed.  相似文献   

16.
The CuI‐catalyzed addition of iodine to the C≡C triple bond of 3,3‐diethoxy‐1‐phenyl propyne ( 1 ) unexpectedly leads to the new cyclization products 2,3‐diiodo‐1H‐inden‐1‐one ( 2 ) and 1‐ethoxy‐2,3‐diiodo‐1H‐indene ( 3 ). Both compounds were isolated and characterized via 1H, 13C NMR (Nuclear Magnetic Resonance) spectroscopy and HRMS (High Resolution Mass Spectrometry). The molecular and crystal structures of compounds 2 and 3 were determined by single crystal X‐ray diffraction. Their crystal structures are governed by extensive halogen bonding, involving I·I and I·O interactions.  相似文献   

17.
The structures of the phosphorus‐boron adducts n‐Pr3P · BBr3 (trigonal, space group P 4 c1, Z = 4, a = 11.5423(6), b = 11.5423(6) and c = 13.8066(7) Å) and I3P · BBr3 (orthorhombic, space group Pnma, Z = 4, a = 12.761(2), b = 11.427(1), c = 7.3728(7) Å) were determined by X‐ray crystallography. The P–B distance of 2.01(1) Å in I3P · BBr3 is significantly longer than the P–B bond in n‐Pr3P · BBr3 (1.95(1) Å). The different Lewis basicity of phosphorus halides, PX3 (X = Cl, Br, I), and alkylphosphines is discussed. The charge transfer and the bond situation in these donor‐acceptor complexes is studied on the basis of NBO analysis. Selected frequencies of n‐Pr3P · BBr3 obtained by Raman and infrared spectroscopy are assigned and compared with the normal modes of I3P · BBr3.  相似文献   

18.
Phase equilibria in the system BaAu–BaPt have been investigated by X‐ray powder diffraction. Depending on composition, three structure types occur, the FeB type for BaAu, and NiAs for BaPt, while the CrB type of structure is adopted in between. The homogeneity range for the CrB type of structure was established to extend from BaPt0.15Au0.85 to BaPt0.90Au0.10. The respective lattice parameters vary linearly, in accordance with Vegard's law. The crystal structure of the new CrB type compounds have been confirmed by X‐ray powder diffraction for the solid solution range, and by single crystal X‐ray diffraction exemplary for the composition BaAu0.5Pt0.5 (Cmcm; a = 4.3915(5) Å; b = 11.9149(12) Å; c = 4.7920(5) Å; Z = 4). BaAu was also established by single crystal structure determination (Pnma; a = 8.3220(10) Å; b = 4.9252(10) Å; c = 6.3844(10) Å; Z = 4) to complete the results. According to ESCA measurements BaAu0.5Pt0.5 and BaAu can be formulated as [Ba2+·0.5e?]·[Au?0.5·Pt2?0.5] and [Ba2+·e?]·[Au?], respectively.  相似文献   

19.
The X‐ray structure of 1,2,4,5‐tetra­hydroxy­benzene (benzene‐1,2,4,5‐tetrol) monohydrate, C6H6O4·H2O, (I), reveals columns of 1,2,4,5‐tetra­hydroxy­benzene parallel to the b axis that are separated by 3.364 (12) and 3.453 (11) Å. Molecules in adjacent columns are tilted relative to each other by 27.78 (8)°. Water mol­ecules fill the channels between the columns and are involved in hydrogen‐bonding interactions with the 1,2,4,5‐tetra­hydroxy­benzene mol­ecules. The crystal structure of the adduct 1,2,4,5‐tetra­hydroxy­benzene–2,5‐di­hydroxy‐1,4‐benzo­quinone (1/1), C6H6O4·C6H4O4, (II), reveals alternating mol­ecules of 1,2,4,5‐tetra­hydroxy­benzene and 2,5‐di­hydroxy‐1,4‐benzo­quinone (both lying on inversion centers), and a zigzag hydrogen‐bonded network connecting mol­ecules in three dimensions. For compound (II), the conventional X‐ray determination, (IIa), is in very good agreement with the synchrotron X‐ray determination, (IIb). When differences in data collection temperatures are taken into account, even the displacement parameters are in very good agreement.  相似文献   

20.
合成了两个新的配合物CuLCl2•2EtOH(1) 和CoLCl2 (2) [L是( S , S )-1,2-二N-甲基苯并咪唑-1,2-二甲氧基-乙烷],并通过单晶X衍射确定它们的结构。配合物1中,L作为三齿[N, N, O]配体,而配合物2 中,L作为二齿[N, N]配体。这两个配合物共同的结构特点都是通过分子内氢键形成2维的格子结构,然后通过分子间的C-H···Cl型氢键和π–π堆积作用形成3维结构。  相似文献   

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