Layered Lanthanum Complex with 3-Nitrophthalic Acid Assembled via Hydrogen Bonds-Synthesis, Structure and Characterization of [LaL(HL)(H2O)3]2·2H2O (H2L = 3-NO2C6H3(CO2H)2)

A new dinuclear centrosymmetric complex [LaL(HL)(H2O)3]2(2H2O (H2L = 3-nitrophthalic acid, NPA) was synthesized in water/ethanol solution and characterized by X-ray diffraction, IR spectrum and TGA-DTA. The complex crystallizes in triclinic system, space group P-1 with a = 8.1549(16), b = 8.8856(18), c = 15.277(3)(A),α= 100.93(3),α= 90.81(3), γ= 104.56(3)°, V = 1049.8(4)(A)3, Z = 1,μ= 2.125 mm-1, Dc＝1.994 g/cm3, R = 0.0259 and wR = 0.0679. Two 3-nitrophthalates(2-) coordinate with the La3 ions in a bridging mode, and two monohydrogen- 3-nitrophthates(1-) and three waters in terminal ways, respectively. Each La3 ion is nine-coordinated to exhibit a distorted tricapped trigonal prism coordination polyhedron. Both the coordinated and crystal waters are involved in the inter- and intramolecular hydrogen bonds. The dinuclear units are linked into a 2D network structure in the ab plane via intermolecular hydrogen bonds along the axes a and b. Two crystal waters fill each rhombic pore of the network. The networks are further packed along the c axis forming a layered supramolecular structure through the C-H…O weak forces between the adjacent sheets. TGA analysis shows the complex undergoes the loss of waters of crystallization and coordination and the decomposition of ligands sequentially.     

Synthesis and Structure Study of Molybdenum Complex Mo[o-NHCOCH_3-m-NO_2C_6H_3COOH]_2_O2Cl_2·PhCl

The crystal and molecular structures of molybdenum complex, Mo [ o- NHCOCH3- m-NO2C6H3COOH]2O2Cl2.PhCl are reported. The crystal belongs to space group Cc of monoclinic system with unit cell parameters:α= 11. 214 (3) A .b= 19. 544 (4 ) A . c = 14. 091 (6) A .β=94.06(3)°,V'=3080.3 A3 and Z=4. The structure was refined to R=0. 061.The coordination number for the Mo atom Is six. The coordination polyhedron formed by four O atoms and two Cl atoms around the Mo atom is a distorted octahedron. Four O atoms and one Mo atom construct a plane. Two benzyl planes in coordinate groups and the benzyl plane of solvent are almost parallel. The quantum-chemical calculations were carried out. There are hydrogen bonds in the Complex. The EHMO calculations and the existence of hydrogen bonds prove that the O atoms are stronger coordinated atoms in the carbonyls than in the carboxyls.     

Synthesis and Crystal Structure of Di-μ_(1,1)-azido-bis((azido)[N-ethyl-N'-(1-pyridin-2-ylmethylidene)ethane-1,2-diamino]cadmium(Ⅱ))

The dinuclear Schiff base cadmium(II) complex [Cd2(C10H15N3)2(N3)2 (μ1,1-N3)2] was prepared and characterized by elemental analysis, IR spectrum, and single-crystal X-ray dif- fraction. The crystal belongs to the monoclinic system, space group P21/n with a = 10.819(2), b = 11.058(2), c = 12.766(3) , β = 102.456(2)o, V = 1491.3(7) 3, Z = 2, Dc = 1.665 g/cm3, Mr = 747.42, λ(MoKα) = 0.71073 , μ = 1.470 mm-1, F(000) = 744, R = 0.0307 and wR = 0.0584. A total of 3420 unique reflections were collected, of which 2575 with I > 2σ(I) were observed. There is a crystallographic inversion centre at the midpoint of the two metal atoms in the complex. Each CdII atom in the complex is in a distorted octahedral coordination. The molecules in the crystal are linked through the intermolecular hydrogen bonds of N–H···N and C–H···N, forming a three- dimensional network.     

Synthesis and Crystal Structure of a Co(Ⅱ) Complex with Taurine-5-methyl-2-hydroxyisophthalaldehyde Schiff Bases [Co(C_(13)H_(16)N_2O_7S_2)(H_2O)_3]_2·H_2O

The title complex CoL(H2O)32·H2O(C26H46N4O21S4Co2),where L = taurine-5-methyl-2-hydroxyisophthalaldehydes,has been synthesized and characterized by IR and X-ray diffraction analysis.The crystal of the complex belongs to the triclinic system,space group P1,with a = 11.197(4),b = 13.309(5),c = 14.486(5),α = 78.827(13),β = 70.547(11),γ = 81.058(13)°,Mr = 996.77,S = 1.08,V = 1987.2(13)3,Z = 2,Dc = 1.666 g/cm3,F(000)= 1032,μ = 1.131 mm?1,R = 0.0633 and wR = 0.1293.According to the structural analysis,the Co(Ⅱ)ion adopts a slightly distorted six-coordinated octahedral geometry.One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom.Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds,thus generating an infinite chain constructed by hydrogen bonds.     

CRYSTAL STRUCTURE OF ERBIUM (HI) COMPLEX WITH 5-SUL-FOSALICYLIC ACID[Er (SO_3C_8H_3(OH)CO_2) (H_2O)_7] [Er (SO_3C_6H_3-(OH)CO_2)_2(H_2O)_6]·8H_2O

<正> [Er(SSA)(H2O)7][Er(SSA)2(H2O)6]·8H2O (H2SSA = 5-sul-fosalicylic acid), Mr=1361.3, monoclinic,P21/c, a = 21.459(7), b = 10.125(2), c = 22. 033(5)(?), β=109. 07(2)°, V = 4524(2)(?)3, Z = 4, D,= 1. 998g/cm3, μ (MoKa) = 40. 6cm-1, F(000)=2704, R = 0. 038 for 5805 observed reflections. The Er(Ⅲ) ions in-both complex cation and anion are coordinated by unidentate SSA ligand(s) and water molecules in a trigondodecahedral geometry. The coordination polyhedra are connected with each other by hydrogen bonds involving the uncoordinated carboxylato oxygen atoms and the coordinated water molecules. Stacking interactions between the phenyl rings further stabilize the structure.     

Syntheses and Crystal Structures of 3-Carboxylsalicylidenefurfurylimine And Its Trinuclear Nickle(Ⅱ) Complex

A Schiff base ligand(H2CSF,C13H11NO4,1) derived from 3-carboxylsalicylaldehyde and furfurylamine,and its trinuclear complex [Ni3(CSF)2(CH3COO)2(DMF)2(H2O)2](2) were synthesized.Compound 1 was characterized by elemental analysis,1H NMR,IR,MS and X-ray diffraction analysis.The crystal of 1 belongs to the monoclinic system,space group P21/c with a = 8.472(2),b = 19.743(5),c = 7.2300(18) ,β = 110.278(4)°,V = 1134.4(5) 3,Z = 4,Mr = 245.23,Dc = 1.436 g·cm-3,μ = 0.108 mm-1,F(000) = 512,λ = 0.71073 ,the final R = 0.0440 and wR = 0.1199 for 1426 observed reflections(I 2σ(I)).In the crystal of 1,there exist intramolecular hydrogen bonds and weak intermolecular C-H···O hydrogen bonds.Compound 2 was characterized by elemental analysis,IR,TG and X-ray diffraction analysis.The crystal of 2 is of triclinic system,space group P1 with a = 10.1237(17),b = 10.4086(18),c = 10.4884(18) ,α = 82.528(2),β = 67.339(2),γ = 83.010(2)°,V = 1008.1(3) 3,Z = 1,Mr = 962.87,Dc = 1.586 g·cm-3,μ = 1.463 mm-1,F(000) = 498,λ = 0.71073 ,the final R = 0.0517 and wR = 0.0805 for 2065 observed reflections(I 2σ(I)).The geometry of the trinuclear molecule is centrosymmetric,in which every Ni(Ⅱ) ion is coordinated in a slightly distorted octahedron.The three Ni(Ⅱ) ions are arranged in a straight line.The two CSF2-ions act as NOO tridentate ligands with the phenolate and carboxylate oxygen as bridging atoms.The coordination atoms of CSF2-anions and water molecules are coordinated on the equatorial plane,while the two bridging acetate ions and two DMF are trans-coordinated on the apical sites.     

STRUCTURE OF { CEu_2 (OOCCH_2NHCOCH_2NH_3)_4 (H_2O)_4]·(C1O_4)_6·4H_2O}_n

<正> {[Eu(OOCCH2NHCOCH2NH3)2(H2O)2]·(ClO4)3·2H2O}2,Mr = 1572,P21/n,a=12. 014(4),b=8. 910(5),c=22. 749(5)A ,β=91. 73(3)°,V = 2034 A3,Z=2,Dx=2. 15g·cm-3,λ(MoKa) = 0. 71073A,R=0. 060 for 3107 unique observed reflections (I≥3σ(I)). The complex cation is of one-dimensional chain structure in which the basic unit is a dinuclear complex and the gly-gly ligands are coordinated to metal atoms in two kinds of forms. The overall structure of the dinuclear unit is dioxo and dicarboxyl-bridged.     

Synthesis and Crystal Structure of a Di-μ_2-phenolic Bridged Binuclear Manganese(Ⅲ) Schiff Base Complex

A new complex [Mn(L)(NCS)]2·0.5CH3CN (H2L = N,N'-bis(chlorosalicylidene)-1,2-diaminoethane) has been synthesized,and its structure (C70H51Cl8Mn4N13O8S4,Mr = 1833.84) was determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system,space group C2/c with a = 25.883(2),b = 12.3320(13),c = 13.5951(16) ,β = 112.906(2),V = 3997.2(7) 3,Z = 2,Dc = 1.524 g/cm3,μ(MoKα) = 1.050mm-1,F(000) = 1852,S = 1.098,the final R = 0.0630 and wR = 0.1847 for 2542 reflections with Ⅰ 2σ(Ⅰ). The centrosymmetric title complex contains a dimer in which two distorted octahedral Mn(Ⅲ) centers are bridged equatorially by phenolic oxygen of the Schiff base ligand. The units of the complex are linked via weak C-H···N hydrogen bonds,leading to the formation of 1D chains along the b axis. The weak π-π packing interactions and weak intermolecular C(3)-H(3)···N(3) hydrogen bonds stabilize the crystal structure.     

Synthesis, Crystal Structure and Photoluminescent Property of a Novel Silver(I) Compound {[Ag(bpp)]_2(Hphth)(NO_3)·(H_2O)_2}_n

Self-assembly of Ag(I) nitrate, 1,3-bis(4-pyridyl)propane (bpp) and phthalic acid monopotassium salt (KHphth) in CH3OH-H2O solution produced the title complex, {[Ag(bpp)]2(Hphth)(NO3)·(H2O)2}n, which was characterized by single-crystal X-ray diffraction, elemental analysis, IR spectrum, and photoluminescent spectrum. Single-crystal X-ray analysis revealed that the complex crystallizes in a monoclinic system, space group P21/c, with a = 15.4174(5), b = 8.6398(2), c = 25.2466(8) , β = 91.072(1)o, V = 3362.34(17) 3, Z = 4, C34H37N5O9Ag2, Mr = 875.43, Dc = 1.729 g/cm3, μ = 1.228 mm-1, F(000) = 1768, the final R = 0.0749 and wR = 0.1580 for 5754 reflections with I > 2σ(I). The Ag atom is coordinated by two N atoms from two bpp molecules in an approximately linear geometry. The Ag(I) ions are linked by the bpp molecules to form one-dimensional zigzag chains propagating along the c axis. The Hphth- and nitrate counter-ions are bridged by solvent water molecules through hydrogen bonds to generate a one-dimensional chain extending along the b axis. Electrostatic interactions between cations and anions, extensive hydrogen bonds and π-π interactions are responsible for the three-dimensional supramolecular structure. In the solid state, the compound exhibits blue photoluminescence with the maximum at 436 nm upon excitation at 344 nm.     

CRYSTAL AND MOLECULAR STRUCTURE OF TETRAAQUA TRIM TRATO SAMARIUM(Ⅲ) DIHYDRATE [Sm(H_2O)_4(NO3)_3] ·2H_2O

<正> [Sm(H2O)4(NO3)3]·2H2O,Mr=444. 46,triclinic,space group P1 ,a = 6.747(1),b=9. 156(1),c=11.673(l) A ,α= 69. 90(1),β=88. 88(1),γ=69. 29 (1)°,V = 629.0A3,Z=2,λ(MoKa) = 0. 7107A,F(000) = 430,Dx=2. 346/cm3,final R=0. 032. The Sm atom in the title complex has bicapped square antiprismtic coordination of oxygen atoms from four water molecules and three NO3 groups. The Sm -O(nitrato) and Sm-O(aqua) distances are in the ranges of 2. 517-2. 716 and 2. 407-2. 432A , respectively. The N-O bond lengths vary between 1. 209 and 1. 265 A with the shortest distances being those involving noncoordinated oxygen atoms. The two lattice water molecules are outside the coordination sphere of the Sm atom but participate in the network of intermolecular hydrogen bonds.     

Synthesis and Crystal Structure of a New Complex {[Co~(Ⅲ)L_2]·[Co~(Ⅱ)(H_2O)_6]_(0.5)·2.25H_2O}_4 (H_2L = N-(2-Hydroxyphenyl)salicylidenimine)

The reaction of Co(OAc)2·4H2O with the Schiff base H2L in a methanol solution affords the red crystals of {[CoIIIL2]·[CoII(H2O)6]0.5·2.25H2O}4 1 (H2L = N-(2-hydroxyphenyl) sali-cylidenimine). The molecular and crystal structures were determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n, C104H114Co6N8O37, Mr = 2421.61, a = 10.625(3), b = 16.335(4), c = 15.265(4) , β = 102.990(4)o, V = 2581.6(11) 3, Z = 1, Dc = 1.558 g/cm3, μ = 1.034 mm-1, F(000) = 1252, R = 0.0414 and wR = 0.1167 for 5889 reflections. The Co(III) atom is six-coordinated by two nitrogen atoms and four oxygen atoms of two tridentate L ligands. The abundant hydrogen bonding interactions extend the complex into a one-dimensional supra-molecular framework. The uncoordinated water molecules act as space-fillers and consolidate the whole architecture through the hydrogen bonding interactions.     

Synthesis and Crystal Structure of a Three-dimensional Manganese(II) Complex (tataH)_2[Mn(pydc)_2]·4H_2O (tata = 2,4,6-Triamino-1,3,5-triazine, pydcH_2 = Pyridine-2,6-dicarboxylic Acid)

A manganese(II) complex (tataH)2[Mn(pydc)2]·4H2O (C20H28MnN14O12, Mr = 711.50, tata = 2,4,6-triamino-1,3,5-triazine, pydcH2 = pyridine-2,6-dicarboxylic acid) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1, with a = 9.9847(3), b = 10.9813(3), c = 15.2616(5) , α = 101.5310(10), β = 90.2610(10), γ = 116.4600(10)°, V = 1459.44(8) 3, Z = 2, Dc = 1.619 g/cm3, μ = 0.539 mm–1, F(000) = 734, the final R = 0.0292 and wR = 0.0745. In the crystal the MnII atom is six-coordinated by four carbonyl oxygen atoms and two pyridine nitrogen atoms from two tridentate pydc ligands to furnish a distorted octahedral geometry. The complex shows the A…D…D’…A’ H-bonded tetramer. The molecules are packed in a three-dimensional framework structure by the combination of O–H…O, N–H…O and N–H…N hydrogen bonds between (tataH)+, [Mn(pydc)2]2– and crystal water.     

Synthesis and Crystal Structure of [{Cd(hmbdc)(H_2O)_3}·2H_2O]_n

A novel coordination polymer [{Cd(hmbdc)(H2O)3}·2H2O]n (hmbdc = 5-hydroxy- isophthalic acid) has been synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c, with a = 9.599(3), b = 18.699(5), c = 7.557(2) , β = 108.198(4)°, V = 1288.6(6) 3, Z = 4, Mr = 382.60, Dc = 1.972 g/cm3, F(000) = 760, μ = 1.740, the final R = 0.0555 and wR = 0.0995 for 1732 observed reflections with I > 2σ(I). The structural analysis shows that the intermolecular hydrogen bonds and π-π interactions result in a three-dimensional supramolecular framework.     

CRYSTAL STRUCTURE OF TRIGALLIUM TRIS(OBTHOPHOSPHATE) 2-ETHANOLANINE HYDRATE, Ga_3(PO_4)_3·H_2NCH_2CH_2OH·H_2O

<正> Trigallium tris(orthophosphate) hydrate-2-ethanolamine was synthesized from the ethanolamine(EAN)-Ga2O3-P2O5-H2O system. The compound crystallizes in monoclinic system, space group P21/n, with a = 8.669(2), b = 17.932(4), c = 9.097(2) A,β= 108.32(1)°,V=1342.4 A3, Z = 4. The structure was solved by direct methods and refined to final R of 0.048. For the three gallium atoms in an asymmetric unit, the coordination tetrahedron of Ga(3) is nearly regular, while Ga(l) and Ga(2) are each coordinated by five oxygen atoms and their coordination polyhedra show some distortion from a trigonal bipyramid. The three-dimensional net in the crystal lattice is built of two-dimensional nets which are composed of irregular triangles, quadrilaterals, pentagons and octagons formed by Ga and P atoms. Moreover, the corrugated 2D nets running along [101] are linked together by two double-crank-shaft chains of GaPO4, one of which runs along [101] while the other along [101]. The ethanolamine molecule, so called the template,     

Synthesis and Crystal Structure of [Cu_2(DMF)(H_2O)(C_7H_4NO_4)_2(C_7H_3NO_4)]_2·3.5DMF

A new copper(II) complex [Cu2(DMF)(H2O)(C7H4NO4)2(C7H3NO4)]2·3.5DMF has been synthesized and its structure was determined by single-crystal X-ray diffraction.The crystal is of triclinic,space group P1 with a = 10.722(3),b = 18.170(4),c = 20.923(7),α = 105.297(9),β = 101.701(10),γ = 105.74(1)°,V = 3615(1) 3,Z = 2,C58.50H64.50Cu4N11.50O31.50,Mr = 1686.90,Dc = 1.550 g/cm3,μ = 1.255 mm-1,F(000) = 1728.00,T = 150(2) K,the final R = 0.0640 and wR = 0.173 for 11310 observed reflections with I > 2σ(I).In the crystal,each formular unit consists of two dinuclear copper(II) compounds,between which the O-H···O hydrogen bonds exist.Each CuII cation is six-coordinated in an octahedral geometry.The intermolecular hydrogen-bonding interaction leads to a 3-D framework of the title compound.     

Synthesis and Crystal Structure of a 1-D Chain Coordination Complex {[Mn2(HCAM)3(H2bipy)]·5H2O}n

The 1-D chain coordination complex of {[Mn2(HCAM)3(H2bipy)]·5H2O}n(H3CAM=4-hydroxypyridine-2,6-dicarboxylic acid,bipy=4,4′-bipyridine) has been synthesized by the reaction of 4-hydroxypyridine-2,6-dicarboxylic acid,4,4′-bipyridine and manganese carbonate under hydrothermal conditions,and its crystal structure was determined by X-ray diffraction method.The crystal belongs to the monoclinic system,space group P21/n with a=10.110(2),b=20.159(4),c=17.861(4) ,β=99.67(3)°,V=3.5884(12) nm3,Mr=901.47,Z=4,Dc=1.669 g·cm-3,μ=0.798 mm-1,F(000)=1840,the final R=0.0713 and wR=0.1853.The complex forms a 1-D chain bridged by HCAM,protonated 4,4-bipyridines link the 1-D chains to construct 2-D networks via N-H…O hydrogen bonds,and networks are further extended via π-π stacking and hydrogen bonds into 3-D supramolecular framework.     

Synthesis and Crystal Structure of a New Lanthanum(III) 4-Cyanobenzoate Complex

A new dinuclear La(III) complex [La2(4-cba)4[H(4-cba)2]2(phen)2(H2O)4] (4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline) 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by single- crystal X-ray diffraction. Crystallographic data: C88H58La2N12O20, Mr = 1881.28, triclinic P1, a = 7.518(3), b = 17.033(6), c = 17.551(6), α = 115.333(4), β = 92.9910(10), γ = 99.366(5)°, V = 1985.3(12)3, Z = 1, Dc = 1.574 g/cm3, F(000) = 944 μ = 1.145 mm–1, the final R = 0.0281 and wR = 0.0686 for 6708 reflections with I > 2σ(I). In 1, two nine-coordinated La(III) ions are connected by two 4-cba ligands in a syn-syn bidentate coordination mode, and the other six 4-cba ligands terminate the La(III) ions, resulting in an isolated dinuclear structure. Two different types of intramolecular hydrogen bonds, asymmetrical O-H…O and symmetrical O…H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 2-D layered network. The thermogravimetric analysis of 1 has also been discussed.     

Hydrothermal Synthesis,Crystal Structure and Thermal Stability Properties of the Complex [Cd_2(phen)_2(C_(14)H_(11)O_3)_4(CH_3CH_2OH)]·(CH_3OH)·(H_2O)

A dinuclear cadmium complex [Cd2(phen)2(C14H11O3)4(CH3CH2OH)]·(CH3OH)·(H2O) has been synthesized with benzilic acid and 1,10-phenanthroline by hydrothermal method.The crystal structure was determined by X-ray diffraction with crystal parameters as follows:triclinic system with space group P1,a = 1.21298(10),b = 1.32586(11),c = 2.4815(2) nm,α = 76.2630(10),β = 81.4500(10),γ = 69.1700(10)o,V = 3.6143(5) nm3,Dc = 1.438 g/cm3,Z = 1,F(000) = 1600,the final GOOF = 0.937,R = 0.0521 and wR = 0.1328.In the title complex,the dinuclear structure is defined by carboxyl oxygen atoms adopting a monodentate bridged coordination mode.The coordination environment of Cd(Ⅱ) ion is CdO4N2,giving a distorted octahedral coordination geometry.TG analysis shows that the title complex is stable under 140 ℃.     

Synthesis, Crystal Structure and Luminescent Properties of [Zn（bipy）_2（H_2O）_4]·L·3H_2O

A novel coordination complex [Zn(bipy)2(H2O)4]·L·3H2O (1, bipy = 4,4'-bipyridine, LHNa = aniline-2,5-disulfonic acid monosodium salt) has been synthesized from LHNa by using hydrothermal method and structurally characterized. The result indicates that complex 1 belongs to the monoclinic system, space group P21/c with a = 20.392(3), b = 7.4052(12), c = 23.843(3) , β = 116.253(10)°, V = 3.2291(8) 3, Z = 4, Dc = 1.553 g·cm-3, μ = 0.962 mm-1, F(000) = 1568, and the final R = 0.0497 and wR = 0.1290. The complex 1 has a 0-D discrete structure, and generates an infinite 3-D network with the aid of O–H…O hydrogen bonds and π-π interactions.     

Synthesis,Crystal Structure and Fluorescent and Thermal Stability Properties of the Zinc(Ⅱ) Complex [Zn(C_(15)H_(11)O_3)_2(C_(12)H_8N_2)_2]·5H_2O

A new complex has been synthesized with o-methylbenzoyl-benzoic acid(HL) and 1,10-phenanthroline(phen) in the mixture of water and ethanol. It crystallizes in monoclinic, space group C2/c with a = 13.6328(18), b = 17.7876(18), c = 19.998(2), β = 104.720(4)o, C54H48N4O11Zn, Mr = 994.33, V = 4690.2(9)3, Dc = 1.408 g/cm3, Z = 4, F(000) = 2072, μ(MoKα) = 0.59 mm-1, R = 0.0736 and wR = 0.2029. The crystal structure shows that the zinc ions are coordinated with two oxygen atoms from two HL molecules and four nitrogen atoms from two phen molecules, forming distorted octahedral coordination geometry. The fluorescent and thermal stability properties of the complex are studied. The result shows that it has one fluorescent emission band at around 412 nm. In addition, the complex is stable under 210 ℃.