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1.
Wilhelm Klein Jan Curda Martin Jansen 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):i63-i64
Pb2(Hg3O4)(CrO4) consists of [CrO4]2− tetrahedra, linear O—Hg—O dumbbells and divalent Pb atoms in [3+5]‐coordination. The HgO2 dumbbells are condensed into [Hg3O4]2− units and can be regarded as a section of the HgO structure. The [Hg3O4]2− complex anions are connected by interstitial Pb2+ ions, while the [CrO4]2− tetrahedra are isolated. 相似文献
2.
Shao‐Hua Luo 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):494-497
The asymmetric unit of the title compound, [Pb2(C8H3IO4)2(CH4O)]n, contains two PbII atoms, two 5‐iodoisophthalate (5‐IIP2−) ligands and one coordinated methanol molecule. One Pb atom is eight‐coordinated, surrounded by seven carboxylate O atoms from five 5‐IIP2− ligands and one O atom from the terminal methanol ligand. The other Pb atom is seven‐coordinated in a hemidirected geometry, surrounded by seven carboxylate O atoms from five 5‐IIP2− ligands. Both Pb atoms are connected by carboxylate groups to form a one‐dimensional infinite rod along the a axis; neighbouring rods are further linked by the aromatic rings of 5‐IIP2− to generate the final three‐dimensional structure with channels in the a direction. An O—H...O hydrogen bond between the methanol ligand and one of the carboxylate groups of a 5‐IIP2− ligand stablizes the three‐dimensional framework. Interestingly, a centrosymmetric rhombus‐shaped I4 unit is formed by four 5‐IIP2− ligands, with I...I distances of 3.8841 (8) and 3.9204 (8) Å. 相似文献
3.
Shao‐Min Cheng Xian‐Fei Wang Fang Yang Hang Chen Wen‐Long Liu 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):693-696
In the title polymer, [Pb(C9H4O6)]n, the asymmetric unit contains a monomer of a PbII cation with a doubly deprotonated 3‐carboxybenzene‐1,2‐dicarboxylate dianion (1,2,3‐Hbtc2−). Each PbII centre is seven‐coordinated by seven O atoms of bridging carboxy/carboxylate groups from five 1,2,3‐Hbtc2− ligands, forming a distorted pentagonal bipyramid. The PbII cations are bridged by 1,2,3‐Hbtc2− anions, yielding two‐dimensional chiral layers. The layers are stacked above each other to generate a three‐dimensional supramolecular architecture via a combination of C—H...O interactions. The thermogravimetric and optical properties are also reported. 相似文献
4.
Lei‐Lei Liu Cai‐Xia Yu Lei Hua Lu Lin 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):650-653
In the title coordination polymer, [Pb(C14H8N2O4)(CH3OH)2]n, the asymmetric unit contains half of a PbII cation, half of a 2,2′‐(diazene‐1,2‐diyl)dibenzoate dianionic ligand (denoted L2−) and one methanol ligand. Each PbII centre is eight‐coordinated by six O atoms of chelating/bridging carboxylate groups from four L2− ligands and two O atoms from two terminal methanol ligands, forming a distorted dodecahedron. The [PbL2(MeOH)2] subunits are interlinked via the sharing of two carboxylate O atoms to form a one‐dimensional [PbL2(MeOH)2]n chain. Adjacent chains are further connected by L2− ligands, giving rise to a two‐dimensional layer, and these layers are bridged by L2− linkers to afford a three‐dimensional framework with a 41263 topology. 相似文献
5.
Fengji Ma Caixia Yu Huijuan Wang Feng Zhao 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(10):934-936
A novel three‐dimensional coordination polymer, {[Pb(C14H8N2O4)(H2O)]·0.5C12H10N2}n, has been synthesized by hydrothermal reaction of Pb(OAc)2·3H2O (OAc is acetate), 2,2′‐(diazene‐1,2‐diyl)dibenzoic acid (H2L) and 1,2‐bis(pyridin‐4‐yl)ethylene (bpe). The asymmetric unit contains a crystallographically independent PbII cation, one L2− ligand, an aqua ligand and half a bpe molecule. Each PbII centre is seven‐coordinated by six O atoms of bridging–chelating carboxylate groups from L2− ligands and by one O atom from a coordinated water molecule. The PbII cations are bridged by L2− ligands, forming [PbO2]n chains along the a axis. These chains are further connected by L2− ligands along the b and c axes to give a three‐dimensional framework with a 41263 topology. The channel voids are occupied by bpe molecules. 相似文献
6.
《Journal of Coordination Chemistry》2012,65(20):3332-3342
[Pb2(tfnb)4 (µ-CH3OH)] n (1) and [Pb2(dmp)2(tfnb)4] (2) (tfnb and dmp are the abbreviations for 4,4,4-trifluoro-1-naphthyl-1,3-butanedionate and 2,9-dimethyl-1,10-phenanthroline) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, and thermal analysis. The single-crystal structure of 1 shows that the complex forms two 1-D polymeric networks containing four types of Pb2+ with coordination numbers seven for Pb(1) and Pb(3), five for Pb(2), and six for Pb(4). The single-crystal structure of 2 shows that the complex forms a dinuclear complex with eight-coordinate Pb(II). The supramolecular features in this complex are guided by lone-pair activity and the control of weak directional intermolecular interactions and aromatic π–π stacking interactions. 相似文献
7.
Dominik Vítek Prof. Aleš Růžička Dr. Libor Dostál Prof. Roman Jambor 《欧洲无机化学杂志》2023,26(5):e202200678
N-coordinated Ge(II) alkoxides L1(tBuO)Ge ( 1 ), L2(tBuO)Ge ( 2 ) and [L2(OtBu)Ge ⋅ BH3] ( 4 ) were prepared. Effect of either chelating ligands L1 and L2 or Ge→B interaction on strength of the Ge−OtBu bond was studied by insertion reaction of PhNCO. As a result, the Ge(II) carbamate L2{[(tBuO)OC](Ph)N}Ge ( 3 ) was isolated. Alcoholysis exchange reactions of 1 and 2 with substituted phenols were studied to find an easy synthetic protocol for a synthesis of functionalized Ge(II) alkoxides. Reactions yielded Ge(II) alkoxides L1,2(2-Br−C6H4O)Ge ( 5 for L1, 8 for L2), L1,2(2-MeNH−C6H4O)Ge ( 6 for L1, 9 for L2), L1,2(2-Ph2P−C6H4O)Ge ( 7 for L1, 10 for L2), L2(2-Br-3-OH−C6H3O)Ge ( 11 ) and L2(2-NC5H4O)Ge ( 12 ) containing the additional polar groups Y (Y=Br, MeNH, PPh2, OH or N). Finally, phosphane decorated Ge(II) alkoxides 7 and 10 were tested as suitable ligands in reactions with (COD)W(CO)4 and BH3. As a consequence, new complexes [(κ2- 7 )W(CO)4] ( 13 ) and [L1(2-Ph2P ⋅ {BH3}-C6H4O)Ge ⋅ {BH3}] ( 14 ) were isolated. All compounds were characterized by NMR and IR spectroscopy, and compounds 3 , 4 , 9 and 11 were additionally characterized by X-ray diffraction analysis. 相似文献
8.
Dr. Mohd Asif Ansari Dr. Mursaleem Ansari Dr. Madhusudan K. Pandey Christian Köhler Dr. Regine Herbst-Irmer Prof. Dr. Dietmar Stalke Prof. Dr. Herbert W. Roesky 《欧洲无机化学杂志》2023,26(24):e202300209
Herein we report the reactions of 3,4,5,6-tetrafluoroterephthalonitrile ( 1 ) with bis(silylene) and bis(germylene) LE−EL [E=Si ( 2 ) and Ge( 3 ): L=PhC(NtBu)2)]. The reaction of LSi−SiL (L=PhC(NtBu)2) ( 2 ) with two equivalents of 1 resulted in an unprecedented oxidative addition of a C−F bond of 1 leading to disilicon(III) fluoride {L(4-C8F3N)FSi−SiF(4-C8F3N)L}( 4 ), wherein the Si−Si single bond was retained. In contrast, the reaction of LGe−GeL (L=PhC(NtBu)2) ( 3 ) with one equivalent of 1 resulted in the oxidative cleavage of Ge−Ge bond leading to L(4-C8F3N2)Ge ( 5 ) and LGeF ( 6 ). All three compounds ( 4 – 6 ) were characterized by NMR spectroscopy, EI-MS spectrometry, and elemental analysis. X-ray single-crystal structure determination of compound 4 unequivocally established that the SiIII−SiIII bond remains uncleaved. 相似文献
9.
New quaternary selenides M2Sb5Bi5Se17 (M = Sn, Pb) were synthesized using solid-state sintering reactions that crystallize in the monoclinic system with C2/m (No. 12) space group with lattice parameters a = 27.914(7) Å, b = 4.0804(11) Å, c = 15.512(4) Å, and β = 114.881(9)° for M = Sn, and a = 27.987(3) Å, b = 4.1062(5) Å, c = 15.6372(19) Å, and β = 115.318(3)° for M = Pb, respectively. The crystal structure is related to a homologous series [A+22x−4B+34 Se−22x−2][B+32y−2Se−23y−3] with (x, y) = (3, 4) that contains building units of two-dimensional slabs of NaCl111-type [Sb2Bi4Se11] separated by 1D ribbons NaCl100-type [Pb2Sb3BiSe6]. The NaCl111 unit contains edge-shared octahedra filled with Sb3+ and Bi3+ cations, which are parallel and overlapped to form a step-layer 2D network stacking alone [001]. The NaCl100 type ribbons containing Pb2+ and Sb3+ in square or trigonal pyramidal environments with the general formula [M6Se6] filled in the space between 2D layers of NaCl111 units. The conductivity measurement revealed semiconducting property with band gaps of ~0.1 eV. Pb2Sb5Bi5Se17 exhibits low thermal conductivity 3,000 μW cm−1 K−1 in a temperature range of 300–480 K. 相似文献
10.
Ya-Shan Huang Yuan Xue Prof. Alvaro Muñoz-Castro Prof. Dr. Ivan A. Popov Prof. Dr. Zhong-Ming Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(62):e202202192
During the past two decades, single-atom-centered medium-sized germanium clusters [M@Gen] (M=transition metals, n>12) have been extensively explored, both from theoretical perspectives and experimental gas-phase syntheses. However, the actual structural arrangements of the Ge13 and Ge14 endohedral cages are still ambiguous and have long remained an unresolved problem for experimental implementation. In this work, we successfully synthesize 13-/14-vertex Ge clusters [Nb@Ge13]3− ( 1 ) and [Nb@Ge14]3− ( 2 ), which are structurally characterized and exhibit unprecedented topologies, neither classical deltahedra nor 3-connected polyhedral structures. Theoretical analysis indicates that the major stabilization of the Ge backbones arises due to the substantial interaction of Ge 4p-AOs with the endohedral Nb 4d-AOs through three/four-center two-electron bonds with an enhanced electron density accumulated over the shortest Nb−Ge13 contact in 1 . Low occupancies of the direct two-center two-electron (2c–2e) Nb−Ge and Ge−Ge σ bonds point to a considerable degree of electron delocalization over the Ge cages revealing their electron deficiency. 相似文献
11.
Xian‐Fa Zhang Shan Gao Li‐Hua Huo Hui Zhao 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):m617-m619
In the title coordination polymer, [Pb(C5H2N2O4)(H2O)]n, the PbII atom is seven‐coordinated by one N atom and five O atoms from four individual imidazole‐4,5‐dicarboxylate (HIDC2−) groups and one water molecule. It is interesting to note that the HIDC2− group serves as a bridging ligand to link the PbII atoms into a three‐dimensional microporous open‐framework. 相似文献
12.
T. I. Ivanova I. V. Rozhdestvenskaya V. S. Fundamenskii I. A. Kasatkin 《Journal of Structural Chemistry》2002,43(1):118-124
The crystals of tetralead hexanitrate ethylenediaminetetraacetatoplumbate(II) tetrahydrate Pb4(NO3)6[PbC10H12O8]4H2O were synthesized and studied by X-ray diffraction (MoK radiation, 2388 reflections, R
F
= 0.0376, R
W
= 0.0348). The orthorhombic unit cell (space group Fdd2, a = 18.995(2), b = 40.649(4), c = 8.5178(8) , Z = 8) contains 16 complex cations [Pb2(NO3)3]2+, 8 complex anions [Pb(Edta)]2–, and 32 crystallization water molecules. The organic and inorganic fragments alternating along the y axis are united into a single frame by the bridging oxygen atoms and by hydrogen bonds. The (Edta)4– ligand, forming one ethylenediamine metallocycle and four glycinate ones, is compressed in the axial direction and stretched in the equatorial direction. The coordination polyhedron of the Pb2+ cation bound with the ligand is a strongly distorted trigonal antiprism. The inorganic fragment is a close-packed double layer of Pb atoms linked with each other by NO3 groups. Thus lead atoms perform a dual function in the structure, forming both complex anions and outer-spheric cations. 相似文献
13.
Dr. Takahito Watanabe Yumi Kasai Prof. Dr. Hiromi Tobita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(59):13491-13495
Reaction of N-heterocyclic carbene (NHC)-stabilized PGeP-type germylene Ge{o-(PiPr2)C6H4}2⋅MeIiPr ( 1 ) (MeIiPr=1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene) with Ni(cod)2 gave pincer germylene complex Ni[Ge{o-(PiPr2)C6H4}2](MeIiPr) ( 2 ), in which the Ge center of 2 is significantly pyramidalized. Theoretical calculation on 2 predicted the ambiphilicity of the germanium center, which was confirmed by reactivity studies. Thus, complex 2 reacted with both Lewis base MeIMe (MeIMe=1,3,4,5-tetramethylimidazol-2-ylidene) and Lewis acid BH3⋅SMe2 at the germanium center to afford the adducts Ni[Ge{o-(PiPr2)C6H4}2⋅MeIMe](MeIiPr) ( 3 ) and Ni[Ge{o-(PiPr2)C6H4}2⋅BH3](MeIiPr) ( 4 ), respectively. Furthermore, the former was slowly converted to dinuclear complex Ni2[Ge{o-(PiPr2)C6H4}2]2(MeIMe)2 ( 5 ) at room temperature. Complex 5 can be regarded as a dimer of the MeIMe analog of 2 with a Ni-Ge-Ge-Ni linkage. 相似文献
14.
Two new coordination polymers of PbII complexes with bridging 4,4′‐[(1E)‐ethane‐1,2‐diyl]bis[pyridine] (ebp), thiocyanato, and acetato ligands, [Pb(μ‐SCN)2(μ‐ebp)1.5]n ( 1 ) and {[Pb(μ‐OAc)(μ‐ebp)](ClO4)}n ( 2 ), were synthesized and characterized by elemental analysis, FT‐IR, 1H‐ and 13C‐NMR, thermal analysis, and single‐crystal X‐ray diffraction. In 1 , the Pb2+ ions are doubly bridged by both the ebp and the SCN− ligands into a two‐dimensional polymeric network. The seven‐coordinate geometry around the Pb2+ ion in 1 is a distorted monocapped trigonal prism, in which the Pb2+ ions have a less‐common holodirected geometry. In 2 , the Pb2+ ions are bridged by AcO− ligands forming linear chains, which are also further bridged by the neutral ebp ligands into a two‐dimensional polymeric framework. The Pb2+ ions have a five‐coordinate geometry with two N‐atoms from two ebp ligands and three O‐atoms of AcO−. Although ClO acts as a counter‐ion, it also makes weak interactions with the Pb2+ center. The arrangement of the ligands in 2 exhibits hemidirected geometry, and the coordination gap around the Pb2+ ion is possibly occupied by a configurationally active lone pair of electrons. 相似文献
15.
Shangxin Wei Dr. Benjamin Peerless Dr. Lukas Guggolz Dr. Stefan Mitzinger Prof. Dr. Stefanie Dehnen 《Angewandte Chemie (International ed. in English)》2023,62(23):e202303037
Pseudo-tetrahedral units of p-block atoms proved to be excellent building blocks for novel molecular architectures and for introducing new elemental combinations which are not otherwise accessible. In this work, we present a series of clusters obtained by reactions of binary Ge/As anions with [MPh2] (M=Zn, Cd, Hg; Ph=phenyl). The study is grounded on the fact that the binary reactant gained by extracting the solid ‘K2GeAs’ with ethane-1,2-diamine (en) co-exists as (Ge2As2)2− and (Ge3As)3− in solution. This allows for a larger variety of products by ‘selecting’ the most suitable species for the final ternary complex to crystallize. The reactions afforded the unprecedented first step of the corresponding interaction, thus attachment of (MPh)+ to a pseudo-tetrahedral unit in [PhZn(Ge3As)]2− ( 1 ) and [PhHg(Ge3As)]2− ( 2 ), and complex anions with two, three, or four units, [(Ge3As)Zn(Ge2As2)]3− ( 3 ), [Cd3(Ge3As)3]3− ( 4 ), and [Zn3(Ge3As)4]6− ( 5 ). Quantum chemistry confirmed the compositions and the positions of the Ge or As atoms, beside explaining structural peculiarities. The subtle impact of different [MR2] reactants was additionally studied by corresponding reactions using [ZnMes2] (Mes=mesityl), which showed success in selectively crystallizing [MesZn(Ge3As)]2− ( 6 ). Based on our findings, we derive a suggestion of the underlying reaction cascade. 相似文献
16.
Reversible Binding of Solvent to Naked PbII Centers in Unusual Homoleptic Alkynyl‐Based Pt2Pb2 Clusters 下载免费PDF全文
Dr. Jesús R. Berenguer Dr. Julio Fernández Dr. Belén Gil Prof. Elena Lalinde Dr. Sergio Sánchez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(9):2574-2584
We report a series of luminescent sandwich‐type clusters [Pt2Pb2(C≡CR)8] (R=Tol, 1 ; C6H4OMe‐3, 2 ; C6H4OMe‐4, 3 ) with a dynamic Pt2Pb2 metallic core, which is key to their intriguing stimuli‐responsive photophysical properties. The solvent‐free solids 1 – 3 display an orange emission ascribed to charge transfer from Pt–alkynyl fragments to a delocalized orbital with mixed Pt2Pb2/C≡CR nature, with a predominant lead contribution and Pb???Pb bonding character (3MLCCT/3IL). They exhibit mechanical, color, and luminescence changes that are reversible and perceivable with the naked eye, which are attributed to small inter‐ and intramolecular structural modifications induced by gentle grinding. Interestingly, 1 and 2 also exhibit remarkable and fast reversible vapochromic responses to donor solvent vapors (acetone, THFMe‐2: yellow; NCMe: green, vs. dry solids: orange). The structures of 1(acetone)2 ?2(Me2CO), 2 ( acetone ) 3 , and 2 ( THFMe ‐ 2 ) 2 allow the vapochromic responses to be ascribed to the fast creation/disruption of solvate clusters [Pt2Pb2(C≡CR)8Sx] (x≥2), with concomitant electronic and geometrical modifications within the Pt2Pb2 core, which are easily accessible through a slight change in the stereochemical activity of the lone pair. The binding of one (or two) solvent molecules to Pb2+ increases the Pb???Pb separation in the metallic core, causing a destabilization of the target orbital and larger energy gaps of the transitions. All the solvates exhibit remarkable rigidochromism upon a decrease in temperature, which is also associated with the gradual increase in the transannular Pb???Pb separation, as revealed by X‐ray crystallography of 1 ( acetone ) 2 at different temperatures. Investigation of the crystal lattice of 1 ?CH2Cl2 and 3 ?2 CH2Cl2 further suggests that the lack of vapor stimuli response of complex 3 could be attributed to the presence of competitive additional secondary intermolecular Pb???O(OMe) contacts, which give rise to a more compact network built up from extended chains of clusters. 相似文献
17.
The reactions of py‐hz ligands ( L1–L5 ) with Pb(CF3SO3)2?H2O resulted in some rare examples of discrete single‐stranded helical PbII complexes. L1 and L2 formed non‐helical mononuclear complexes [Pb L1 (CF3SO3)2]?CHCl3 and Pb L2 (CF3SO3)2][Pb L2 CF3SO3]CF3SO3?CH3CN, which reflected the high coordination number and effective saturation of PbII by the ligands. The reaction of L3 with PbII resulted in a dinuclear meso‐helicate [Pb2 L3 (CF3SO3)2Br]CF3SO3?CH3CN with a stereochemically‐active lone pair on PbII. L4 directed single‐stranded helicates with PbII, including [Pb2 L4 (CF3SO3)3]CF3SO3?CH3CN and [Pb2 L4 CF3SO3(CH3OH)2](CF3SO3)3?2 CH3OH?2 H2O. The acryloyl‐modified py‐hz ligand L5 formed helical and non‐helical complexes with PbII, including a trinuclear PbII complex [Pb3 L5 (CF3SO3)5]CF3SO3?3CH3CN?Et2O. The high denticity of the long‐stranded py‐hz ligands L4 and L5 was essential to the formation of single‐stranded helicates with PbII. 相似文献
18.
19.
A new three-dimensional polymeric PbII complex involving holo- and hemidirected coordination spheres
《Solid State Sciences》2007,9(2):155-158
A new three-dimensional polymeric PbII complex, [Pb3(bpy)(H2O)5(sip)2]n·0.5bpy·2H2O (bpy = 2,2′-bipyridine and sip = 5-sulfoisophethalate), has been synthesized and characterized. Its single-crystal X-ray structure shows three types of Pb2+-ions with coordination numbers of 8 Pb1, 6 Pb2, and 7 Pb3. The Pb1 center with a coordination number of 8 possesses a stereo-chemically ‘inactive’ electron lone pair, and the coordination sphere is holodirected. However, the arrangement of O- and N-atoms for Pb2 and Pb3 suggests a gap or hole in the coordination geometry around these atoms. The stereo-chemically ‘active’ electron lone pairs of Pb2 and Pb3 possibly occupy these ‘holes’, and their coordination spheres are, thus, hemidirected. 相似文献
20.
Ganesan Prabusankar Dr. Christian Gemel Dr. Manuela Winter Rüdiger W. Seidel Roland A. Fischer Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(20):6041-6047
Heavy‐metal complexes of lead and mercury stabilized by Group 13 ligands were derived from the oxidative addition of Ga(ddp) (ddp=HC(CMeNC6H3‐2,6‐iPr2)2, 2‐diisopropylphenylamino‐4‐diisopropyl phenylimino‐2‐pentene) with corresponding metal precursors. The reaction of Me3PbCl and Ga(ddp) afforded compound [{(ddp)Ga(Cl)}PbMe3] ( 1 ) composed of Ga? PbIV bonds. In addition, the monomeric plumbylene‐type compound [{(ddp)Ga(OSO2CF3)}2Pb(thf)] ( 2 a ) with an unsupported Ga‐PbII‐Ga linkage was obtained by the reaction of [Pb(OSO2CF3)3] with Ga(ddp) (2 equiv). Compound 2 a falls under the rare example of a discrete plumbylene‐type compound supported by a nonclassical ligand. Interesting structural changes were observed when [Pb(OSO2CF3)3] ? 2 H2O was treated with Ga(ddp) in a 1:2 ratio to yield [{(ddp)Ga(μ‐OSO2CF3)}2(OH2)Pb] ( 2 b ) at below ?10 °C. Compound 2 b consists of a bent Ga‐Pb‐Ga backbone with a bridging triflate group between the Ga? Pb bond and a weakly interacting water molecule at the gallium center. Similarly, the reaction of mercury thiolate Hg(SC6F5) with Ga(ddp) (2 equiv) produced the bimetallic homoleptic compounds anti‐[{(ddp)Ga(SC6F5)}2Hg] ( 3 a ) and gauche‐[{(ddp)Ga(SC6F5)}2Hg] ( 3 b ), respectively, with a linear Ga‐Hg‐Ga linkage. Compounds 1 – 3 were structurally characterized and these are the first examples of compounds comprised of Ga? PbII, Ga? PbIV, and Ga? Hg bonds. 相似文献