Darstellung und Struktur der Tetrafluoroaurate(III) MI[AuF4] mit MI = Li,Rb

Synthesis and Structure of Tetrafluoroaurates(III) M^I[AuF₄] with M^I = Li, Rb Single crystal investigations on Rb[AuF₄], light yellow, confirm the tetragonal unit cell (K[BrF₄]-type) with a = 618.2(1) and c = 1191(1) pm, Z = 4, space group I 4/mcm-D (No. 140). Li[AuF₄], light yellow too, crystallizes monoclinic with a = 485.32(7), b = 634.29(8), c = 1004.43(13) pm, β = 92.759(12), Z = 4; space group P 2/c-C (No. 13). The structure of Li[AuF₄] is related to the Rb[AuF₄]-type of structure.     

Ag2+ in trigonal-bipyramidaler Umgebung: Neue Fluoride mit zweiwertigem Silber: AgMMF20 (MII = Cd,Ca, Hg; MIV = Zr,Hf)

Ag²⁺ in Trigonal-Bipyramidal Surrounding New Fluorides with Divalent Silver AgM M F₂₀ (M^II = Cd, Ca, Hg; M^IV = Zr, Hf) The intensively green compounds AgMMMF₂₀ (M^II = Cd, Ca, Hg; M^IV = Zr, Hf) have been obtained for the first time as single crystals and investigated by X-ray methods. They crystallize in space group P6₃/m-C_6h² (Nr. 176) with

• a = 1052.0(2) pm, c = 828.6(2) pm (AgCd₃Zr₃F₂₀),
• a = 1048.0(2) pm, c = 832.6(3) pm (AgCd₃Hf₃F₂₀),
• a = 1059.4(2) pm, c = 841.0(3) pm (AgCa₃Zr₃F₂₀),
• a = 1053.7(2) pm, c = 830.6(3) pm (AgCa₃Hf₃F₂₀),
• a = 1058.9(3) pm, c = 832.6(4) pm (AgHg₃Zr₃F₂₀),
• a = 1056.9(2) pm, c = 833.0(3) pm (AgHg₃Hf₃F₂₀), Z = 2.

     

Neue Fluoroaurate(III)

New Fluoroaurates(III) For the first time single crystals of M^II[AuF₄]₂with M^II = Mg, Ni, Zn, Ba, Cd, Hg, Pd have been obtained. Ba[AuF₄]₂ crystallizes tetragonal with a = 978,8, c = 760.0 pm, Z = 4, spcgr. I4 -S²₄ (No. 82), the isotypic compounds Mg[AuF₄]₂ with a = 548.9, b = 552.1, c = 1079.2 pm, β = 109.4°, Zn[AuF₄]₂ with a = 548.7, b = 551.8, c = 1083.1 pm, β = 109.3° and Ni[AuF₄]₂ with a = 545.4, b = 545.7, c = 1073.6 pm, β = 109.6° are monoclinic, spcgr. P2₁/c? C⁵_2h (No. 14), Z = 2. From single crystal photographs Cd[AuF₄]₂ with a = 811.3, c = 1031.2 pm and Hg[AuF₄]₂ with a = 811.7, c = 1039,1 pm, both isotypic, are tetragonal-primitive, Pd[AuF₄]₂ is orthorhombic with a = 517.9, b = 545.5, c = 1092.0 pm.     

Synthese,Struktur und magnetische Eigenschaften der Verbindungen NaMIIZr2F11 (MII = Ti,V und Cu) und einem Anhang über NaPdZr2F11

Synthesis, Structure, and Magnetic Properties of Compounds NaM^IIZr₂F₁₁ (M^II = Ti, V, Cu) and a Notice on NaPdZr₂F₁₁ By synthesizing NaTiZr₂F₁₁ in form of red single crystals, it was possible to obtain a complex fluoride with Ti²⁺ for the first time. It crystallizes like the analogous greenish blue vanadium compound isotypic to AgPdZr₂F₁₁ [1] monoclinic, spacegroup C2/m–C (No. 12) with a = 918.0/911.5 pm, b = 682.6/675.7 pm, c = 780.8/776.6 pm, β = 116.2/116.2º and Z = 2. Colourless NaCuZr₂F₁₁ however crystallizes as a result of the Jahn-Teller distortion of Cu²⁺ triclinic (space group P1 –C (No. 2), a = 552.7 pm, b = 568.2 pm, c = 768.0 pm, α = 111.0º, β = 97.4º, γ = 106.4º) and is – as expected – isotypic to NaAgZr₂F₁₁ [1].     

Zur Kristallstruktur von La[AuF4]3, dem Anfangsglied der Reihe M[AuF4]3−xFx (x = 0, 0,5 und 1)

On the Crystal Structure of La[AuF₄]₃, the Final Link in the Series M[AuF₄]_3?xF_x (x = 0, 0.5 and 1) Yellow La(AuF₄)₃ was prepared for the first time in form of single crystals and investigated by X-ray methods. It crystallizes in space group R3 c-D (Nr. 167) with a = 1056.2(2) pm, c = 1633.7(8) pm, Z = 6.     

Synthese und Struktur von Silber(II)-tetrafluoroaurat(III) Ag[AuF4]2

Synthesis and Structure of Silver(II) Tetrafluoroaurate(III) Ag[AuF₄]₂ Intensive green single crystals of Ag[AuF₄]₂ can be obtained by heating up micro crystalline Ag[AuF₄]₂ in autoclaves (p(F₂) ～ 200 bar, T ～ 400°C, t ～ 14 d). It crystallizes monoclinic, space group P2₁/n ? C; (No. 14) with a = 522.3(1), b = 1101.3(3), c = 550.5(2) pm, β = 94.98(3), Z = 2 and is isotypic with Pd[AuF₄]₂.     

Tetrafluoroaurate(III) der Lanthaniden MF[AuF4]2 (M = Tm,Yb, Lu)

Tetrafluoroaurates(III) of Lanthanides MF[AuF₄]₂ (M = Tm, Yb, Lu) . Tetrafluoroaurates(III) MF[AuF₄]₂ with M = Tm, Yb, Lu, all yellow, have been prepared for the first time. From single crystal data they crystallize orthorhombic, space group Pbcn-D (No. 60) with M = Tm: a = 1 102.92(8) pm, b = 904.38(8) pm, c = 2 164.46(23) pm; M = Yb: a = 1 100.98(12) pm, b = 902.23(8) pm, c = 2 157.36(23) pm; M = Lu: a = 1 099.28(18) pm, b = 900.70(15) pm, c = 2 151.50(46) pm.     

Synthese und Struktur neuer Tetrafluoroaurate(III), TlF2[AuF4], M2F[AuF4]5 (M = Bi,La, Y) und Sm[AuF4]3

Synthesis and Structure of Tetrafluoroaurates(III), TlF₂[AuF₄], M₂F[AuF₄]₅ (M = Y, La, Bi), Sm[AuF₄]₃ with an Appendix on Sm[AuF₄]₂ In the system MF₃/AuF₃ the structures of several yellow Tetrafluoroaurates(III) have been determinated. TlF₂[AuF₄] crystallizes tetragonal, space group P4₁2₁2 – D (Nr. 92) with a = 573.17(4) pm, c = 2780.4(3) pm, Z = 8; M₂F[AuF₄]₅ (M = Bi, La) tetragonal, space group P4₁2₁2 – D (Nr. 92) with a = 822.89(5) pm, c = 2557.1(3) pm, Z = 4 (Bi); with a = 836.80(3) pm, c = 2602.2(2) pm, Z = 4 (La); Y₂F[AuF₄]₅ monoclin, space group P2/n – C (Nr. 13) with a = 1188.9(3) pm, b = 797.4(2) pm, c = 895.7(3) pm, β = 89.18(3), Z = 4 and Sm[AuF₄]₃ trigonal, space group R3c – D (Nr. 167) with a = 1034.5(1) pm, c = 1614.1(3) pm, Z = 6. All these yellow crystals have been obtained by solid state reactions in autoclaves or sealed goldtubes.     

Zur Kenntnis von NiPtF6 und CdPtF6

Anotation to Compounds MPtF₆ (M = Ni, Cd) Yellow single crystals of M¹¹PtF₆ (M¹¹ = Ni, Cd) have been obtained for the first time and investigated by X-ray methods. The powder data of the compounds are confirmed. Both samples are isostructural to LiSbF₆, space group R3 -C (Nr. 148) with a = 500.5(3) pm, c = 1375.6(7) pm for NiPtF₆ and a = 511.56(9) pm, c = 1460.3(4) pm for CdPtF₆, Z = 3.     

Die Kristallstruktur von KPdMIVF7 (MIV = Zr,Hf)

The Crystal Structure of KPdM^IVF₇ (M^IV = Zr, Hf) Blue single crystals of KPdZrF₇ are obtained by heating the binary fluorides in sealed Pt-tubes under dry argon (solid state reaction, T ≈? 720°C, t ≈? 14 d). The compound crystallizes orthorhombically in the space group Pnna-D (Nr. 52); lattice parameters are a = 1 132.3(5) pm, b = 797.5(2) pm, c = 639.8(1) pm; Z = 4 (Four cycle diffractometer data, AED2). According to [F₄PdF_2/1ZrF₅] distortet [PdF₆]-octaedra are connected with pentagonal-bipyramidal [ZrF₇]-polyhedra via two bridging F^?, resulting in [PdZrF₁₁]-groups. These [PdZrF₁₁]-groups built up a threedimensional-network with K⁺ in its spacings. KPdHfF₇ crystallizes isotypically (a = 1 136.1(3) pm, b = 796.4(2) pm und c = 638.8(1) pm; four cycle diffractometer data, AED2).     

Zur Addition von Übergangsmetallhalogeniden an Acetylacetonate zweiwertiger Metallionen

Addition of Transition Metal Dihalides to Acetylacetonates of Divalent Metal Ions Transition metal dihalides ^aM^IIX₂ (FeCl₂, CoCl₂ NiBr₂ etc.) are added by the chelates M^II(acac)₂ under formation of binuclear complexes (THF)₂M^II(acac)₂(^aM^IIX₂). The octahedral and the tetrahedral centre of these compounds are connected by tridentate oxygen atoms of the two acetylacetonato ligands which are simultaneously included in four-membered rings (M^IIOM^II). The addition is combined with a deformation of the octahedral centre, as a prerequisite of a closest package of the atoms within the M^IIOM^II-ring. In the trinuclear complex (THF)₂Ni(acac)₂(HgCl₂)₂ III the interaction between the three coordination centres is weak. No structural change of the octahedral centre (THF)₂Ni(acac)₂ is found, but the HgCl₂-groups diverge slightly from linearity (Cl? Hg? Cl 171.1°). No binuclear complexes with a central ion of the oxidation state III in the octahedral centre were obtained. One reason is the lowered donor strength of the bidentate Lewis base function of the octahedral centre [(THF)₂Mⁿ⁺(acac)₂]^n-2 with M⁺³ as a centralatom. Reacting systems with di- and trivalent ions prefer ionic complexes, as it is shown by the formation of [(THF)₂V(acac)₂][(THF)CoCl₃] IV from VCl₃ and Co(acac)₂. The crystal structures of (THF)₂Co(acac)₂CoCl₂ II and [(THF)₂V(acac)₂][(THF)CoCl₃] IV were determined by x-ray diffraction. II : orthorhombic-primitive; space group P2₁2₁2₁, Z = 4; a = 967.4(2), b = 1453.4(3), c = 1715.9(4) pm; R = 0.049 for 3084 observed reflections. IV : triclinic; space group P1, Nr. 2; Z = 2; a = 871,5(2), b = 930,6(3), c = 1865,6(6) pm; α = 101,70(2), b? = 92,45(2), γ = 91,06(2)°; R = 0,060 für 4221 observed reflections.     

Ba[CoN]: Ein niedervalentes Nitridocobaltat mit gewinkelten Ketten [CoN2/22−]

Ba[CoN]: A Low-Valency Nitridocobaltate with Angled Chains [CoN_2/2^2?] Ba[CoN] is prepared by reaction of barium and cobalt (molar ratio Ba : Co = 1 : 2.5) in tantalum crucibles at 870°C with flowing nitrogen (1 atm) within a period of 96 h. After cooling down to room temperature (24°C/h) black single crystals of the ternary phase with a platy habit are obtained (orthorhombic, Pnma; a = 959.9(2) pm, b = 2 351.0(3) pm, c = 547.6(2) pm; Z = 20). The crystal structure of Ba[CoN] contains angled (planar) chains [CoN_2/2^2?] which run along the [010]-direction (N? Co? N[°]: 178.5(5), 179.6(6), 180.0; Co? N? Co[°]: 82.9(6), 84.2(5), 177.1(8); Co? N[pm]: 174.6(12), 177.2(12), 181.9(13), 184.3(13), 187.1(12)). Nitrogen is in an octahedral coordination (N Ba₄Co₂) and is arranged in a distorted cubic close packing. Barium occupies one half of the tetrahedral holes (Ba? N[pm]: 274.8(16) ? 308.2(12)). The cis-positions of the Co-atoms at the nitrogen coordination-octahedra cause short Co? Co contacts within the chains [CoN_2/2^2?]. Through this, Co₂-units (Co? Co[pm]: 247.8(4); bridged by nitrogen) and linear Co₃-groups (Co? Co [pm]: 245.5(2); Co? Co? Co[°]: 180.0; bridged by nitrogen) alternate along the chains. The crystal structure of Ba[CoN] is closely related to the Ba[NiN] type structure.     

Cs[Er10(C2)2]I18 und [Er10(C2)2]Br18: zwei neue Beispiele für „reduzierte”︁ Halogenide der Lanthanide mit isolierten [M10(C2)2]-Clustern

Cs[Er₁₀(C₂)₂]I₁₈ and [Er₁₀(C₂)₂]Br₁₈: Two New Examples for Reduced Halides of the Lanthanides with Isolated [M₁₀(C₂)₂] Clusters Cs[Er₁₀(C₂)₂]I₁₈ is obtained from the reaction of ErI₃ with caesium and carbon in sealed tantalum containers at 700°C and [Er₁₀(C₂)₂]Br₁₈ through the metallothermic reduction of ErBr₃ with rubidium in the presence of carbon at 750°C in sealed niobium containers. The crystal structures {Cs[Er₁₀(C₂)₂]I₁₈: triclinic, P1 ; a = 1 105.2(8) pm, b = 1 112.0(7) pm; c = 1 122.9(8) pm; α = 66.91(3)°, β = 87.14(3)°; γ = 60.80(3)°; Z = 1; R = 0.049, R_w = 0.043; [Er₁₀(C₂)₂]Br₁₈: monoclinic, P2₁/n, a = 971.8(6) pm, b = 1 623.4(9) pm, c = 1 163.8(6) pm, β = 104.00(6)°; Z = 2; R = 0.077, R_w = 0.057} contain isolated dimeric [Er₁₀(C₂)₂] clusters. Due to the inclusion of C₂ units, the octahedra are elongated in the direction of the pseudo C₄ axis. The connecting edges of the two octahedra are exceptionally short (316.7 pm and 314.8 pm respectively). The dimeric units are connected via X^i?a and X^a?i (X = Br, I) bridges according to [Er₁₀(C₂)₂XX]X. Cs⁺ is surrounded by a cuboctahedron of iodide ions in Cs[Er₁₀(C₂)₂]I₁₈.     

Neue Komplexe Fluoride mit Ag2+ und Pd2+: NaMIIZr2F11 (MII = Ag,Pd) und AgPdZr2F11

New Complex Fluorides with Ag²⁺ and Pd²⁺: NaM^IIZr₂F₁₁ (M^II = Ag, Pd) and AgPdZr₂F₁₁ For the first time single crystals of NaAgZr₂F₁₁, NaPdZr₂F₁₁ and AgPdZr₂F₁₁ have been obtained and investigated by X-ray methods. The isotypic compounds NaM^IIZr₂F₁₁ (M^II = Ag, Pd) crystallize triclinic, spcgr. P1 ? C (No. 2) with a = 780.9, b = 570.0, c = 583.2 pm, α = 106.1°, β = 112.2°, γ = 97.9° (NaPdZr₂F₁₁), AgPdZr₂F₁₁ is monoclinic, spcgr. C2/m? C_2h (No. 12) with a = 935.1, b = 699.1, c = 780.1 pm, β = 115.7°, Z = 2 (Four circle diffractometer data, Siemens AED 2). Their structure is closeley related to the Ag₃Hf₂F₁₄-type of structure.     

Nitridsulfidchloride der Lanthanide: II. Der Formeltyp M6N3S4Cl (M = La?Nd)

Nitride Sulfide Chlorides of the Lanthanides. II. The Composition M₆N₃S₄Cl (M = La? Nd) The oxidation of the “light” lanthanides (M = La? Nd) with sulfur and NaN₃ in the presence of the chlorides MCl₃ yields chlorine-poor nitride sulfide chlorides with the composition M₆N₃S₄Cl when appropriate molar ratios of the reactants are used. Additional NaCl as a flux secures complete and fast reactions (7 d) at 850°C in evacuated silica vessels as well as single-crystalline products (red-brown needles). The crystal structure was determined from X-ray single crystal data for the limiting representatives La₆N₃S₄Cl (orthorhombic, Pnma (no. 62), Z = 4, a = 1159.7(4), b = 410.95(7), c = 2756.8(9)pm, R = 0.030, R_w = 0.027) and Nd₆N₃S₄Cl (a = 1137.1(3), b = 399.34(6), c = 2687.6(9)pm, R = 0.034, R_w = 0.033). Guinier powder data revealed the cerium and praseodymium analogues to be isotypic. The crystal structure exhibits two different chains of connected [NM₄] tetrahedra which are commensurate in translation. Six crystallographically different M³⁺ are present, two of them (M1 and M2) build up the chain [(N1)(M1) · (M2)]³⁺ together with (N1)^3? by cis-edge connection of tetrahedra. The four remainders (M3? M6) arrange as pairs [N₂M₆] of edge-shared [NM₄] tetrahedra with (N2)^3? and (N3)^3? which are further connected via four vertices to form the [(M5)(N-2){(M3)_(1+1)/(1+1)(M4)_(1+1)/(1+1))}^e(N3)(M6)]⁶⁺ double chain. Bundled along [010] like a closest packing of rods, both types of chains are held together by five crystallographically different but by X-ray diffraction indistinguishable anions S^2? (S1? S4) and Cl^? adjusting the charge balance in a molar ratio of 4:1.     

Die Kristallstruktur von Perowskiten ANiIIMVIO6. II. Das Sr2NiWO6

The Crystal Structure of Perovskites A Ni^IIM^VIO₆. II. Sr₂NiWO₆ The results of an X-ray single crystal study of the perovskite Sr[Ni^IIW^VI]⁽⁶⁾O₆, ordered in the octahedral sites, are given. While Sr[Ni^IITe^VI]⁽⁶⁾O₆ crystallizes in a monoclinically deformed structure of the perovskite (elpasolite) type, showing a phase transition to a tetragonal lattice at 675 °K, Sr[Ni^IIW^VI]⁽⁶⁾O₆ is tetragonal already at 298°K (space group: C; a = b = 5.559 Å; c = 7.918 Å; Z = 2). The Ni? O distances found for the tungsten compound are nearly identical with those of the tellurium perovskite. In contradiction to crystal field theory very different values of the ligand field parameter Δ (ca. 25%) are observed for these two compounds however. Obviously this effect is caused by the rather different kind of bonding within the NiO₆ polyhedra in the two compounds. On the basis of the structural results the Ni? O-bonding in the two perovskites is discussed in dependence of the next nearest cationic environment.     

Über grünes Bis-(2-Iminoisopropyl-thiophenolato)-nickel(II) und weitere, ähnliche NiII-Komplexe

Green Bis-(2-iminoisopropyl-thiophenolato)nickel(II) and other Similar Ni^II Complexes The compounds [Ni^II(iitp)₂] 1 (iitp = 2-iminoisopropyl-thiophenolate), [Ni(imptp)₂] · 2 CH₃OH 2 , a dinuclear compound with an Ni? Ni distance of 276 pm, and [PPh₄] · [Ni^II(imptp)(SCN)] 3 (imptp = 2-(2-iminopentane-4-on)-thiophenolate) have been prepared by the reaction of nickel(II)-acetate-tetrahydrate with 2-iminoisopropyl-thiophenole and 2-(2-iminopentane-4-on)-thiophenole in methanol, respectively. They have been characterized by single-crystal X-ray structure analysis and other physical methods. The redox behaviour of 1–3 has been studied in detail (chemically as well as by cyclovoltammetry and ESR spectroscopy). Particularly interesting are the electronic properties of 1 and its reduction with NaBH₄ and the following reaction of the product with O₂. The complexes are model compounds for some Ni-containing enzymes. For details of the crystal structure determination see “Inhaltsübersicht”.     

Synthese und Strukturuntersuchungen von Iodocupraten(I). XV Iodocuprate(I) mit solvatisierten Kationen: [Li(CH3CN)4][Cu2I3] und [Mg{(CH3)2CO}6][Cu2I4]

Synthesis and Structure Investigations of Iodocuprates(I). XV Iodocuprate(I) with Solvated Cations: [Li(CH₃CN)₄] [Cu₂I₃] and [Mg{(CH₃)₂CO}₆][Cu₂I₄] [Li(CH₃CN)₄][Cu₂I₃] 1 and [Mg((CH₃)₂CO)₆][Cu₂I₄] 2 were prepared by reactions of CuI with LiI in acetonitrile and of CuI with MgI₂ in acetone. 1 crystallizes orthorhombic, Pnma, a = 552.7(2), b = 1258.8(8), c = 2516(1) pm, z = 4. [Li(CH₃CN)₄]⁺ cations are located between rod packings of CuI₄ tetrahedra double chains [(CuI_2/2I_2/4)₂]^? parallel to the axis. Short intermolecular anion/cation contacts were observed. The crystal structure of 2 (monoclinic, P2₁/n, a = 1840(2), b = 1059.2(2), c = 1879(2)pm, β = 112.94(4)°, z = 4) is built up by [Mg((CH₃)₂CO)₆]²⁺ cations forming a simple hexagonal sphere packing. The binuclear anions [Cu₂I₄]^2? occupy holes in the trigonal prismatic channels formed by the cations.     

Zur Kenntnis komplexer Fluoride mit Cu2+ und Pd2+: MPtF6 (M  Pd,Cu) und RbCuPdF5

On Complex Fluorides with Cu²⁺ and Pd²⁺: MPtF₆ (M ? Pd, Cu) and RbCuPdF₅ For the first time single crystals of PdPtF₆ (green), trigonal-rhomboedric, a = 503.8, c = 1431.6 pm, spcgr. R3 ? C (No. 148), Z = 3, CuPtF₆ (orange), triclinic, a = 495.2, b = 498.5, c = 962.4 pm, α = 89.98, β = 104.23, γ = 120.35°, spcgr. P1 ? C (No. 2), Z = 2 and RbCuPdF₅ (orange brown, in connection with investigations on M^IPd₂F₅ [1]), orthorhombic, a = 626.9, b = 719.9, c = 1076.3 pm, spcgr. Pnma? D (No. 62), Z = 4, four circle diffractometer data, have been obtained.     

Zur Insertion in die Lanthanoid–Kohlenstoffbindung Synthese und Struktur von [CpSm(C6H5CH2NNO)]2 und [K(18-Krone-6)CpYb(NCS)2]∞

On the Insertion into the Lanthanide–Carbon Bond. Synthesis and Structure of [Cp Sm(C₆H₅CH₂NNO)]₂ and [K(18-crown-6)Cp Yb(NCS)₂]_∞ The compound [CpSm(CH₂C₆H₅)(thf)] was investigated, regarding its reactions with small molecules. The main subject was to detect an insertion into the Ln–C bond. With N₂O an insertion reaction is observed, yielding the dimer [CpSm(C₆H₅CH₂NNO)]₂ ( 1 ). The structural data of 1 was collected by a single crystal X-Ray diffraction analysis. (Space group P 1, Z = 1, a = 982.8(2) pm, b = 1052.2(2) pm, c = 1383.8(3) pm, α = 89.29(3)°, β = 73.64(3)°, γ = 66.41(3)°). In the dimer, the two Samarium ions are linked via an (η¹ : η²) bridge by two benzyl diazotato ligands. A nearly planar six-membered central Sm₂N₂O₂-ring is formend. Two pentamethylcyclopentadienyl ligands complete the coordination sphere of each Samarium ion, which are thus surrounded by four ligands each and have a distorted tetrahedral coordination geometry. An insertion of a SCN^– fragment in the Ln–C bond could not be observed. The substitution of the benzyl ligand leads to a polymeric chain structure. The new compound [K(18-crown-6)CpYb(NCS)₂]_∞ 2 contains a tetrahedrally coordinated Yb(III)-ion. (Space group P2₁/n}, Z = 4, a = 1640.6(3) pm, b = 1482.2(3) pm, c = 1674.5(3) pm, β = 102.82(1)°).