![Syntheses, Crystal Structures and Magnetic Properties of Two Cyano-Bridged Two-Dimensional Assemblies [Fe(Salpn)]2 [Fe(CN)5NO] and [Fe(Salpn)]2[Ni(CN)4]](http://data.docslib.org/img/1a8fbc2262299ccf31c8a7db2f0a4809-1.webp)
Transition Metal Chemistry 29: 100–106, 2004. 100 2004 Kluwer Academic Publishers. Printed in the Netherlands.
Syntheses, crystal structures and magnetic properties of two cyano-bridged two-dimensional assemblies [Fe(salpn)]2 [Fe(CN)5NO] and [Fe(salpn)]2[Ni(CN)4]
Xiao-Ping Shen and Zheng Xu* Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, PR China
Ai-Hua Yuan Department of Material and Environmental Engineering, East China Shipbuilding Institute, Zhenjiang 212003, PR China
Zi-Xiang Huang State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China
Received 13 May 2003; accepted 07 July 2003
Abstract
III II III II Two cyano-bridged assemblies, [Fe (salpn)]2[Fe (CN)5NO] (1) and [Fe (salpn)]2[Ni (CN)4] (2) [salpn ¼ N, N¢- 1,2-propylenebis(salicylideneiminato)dianion], have been prepared and structurally and magnetically characterized. 2) 2) + In each complex, [Fe(CN)5NO] or [Ni(CN)4] coordinates with four [Fe(salpn)] cations using four co-planar ) + 2) 2) CN ligands, whereas each [Fe(salpn)] links two [Fe(CN)5NO] or [Ni(CN)4] ions in the trans form, which II III results in a two-dimensional (2D) network consisting of pillow-like octanuclear [AM ACNAFe ANCA]4 units 2) (M ¼ Fe or Ni). In complex (1), the NO group of [Fe(CN)5NO] remains monodentate and the bond angle of FeIIANAO is 180.0 . The variable temperature magnetic susceptibilities, measured in the 5–300 K range, show weak intralayer antiferromagnetic interactions in both complexes with the intramolecular iron(III) iron(III) exchange integrals of )0.017 cm)1 for (1) and –0.020 cm-1 for (2), respectively.
Introduction been studied structurally and magnetically [11–16]. These complexes exhibit fascinating structures ranging In recent years, an enormous amount of research work from discrete entities to 3D extended networks, and has been devoted to the study of cyano-bridged coor- interesting magnetic properties, such as magnetic order- dination polymers due to their potential use as func- ing and high spin ground states. For example, the tional solid materials, such as catalysts, optical devices reaction between [M¢(BS)]+ (M¢ ¼ Mn, Fe; BS ¼ Schiff 3) as well as molecular-based magnets [1–5]. It is known base ligand) and [M(CN)6] (M ¼ Fe, Cr) has already that the cyano-bridged 3D bimetallic assemblies of the led to a variety of lattice structures depending on the Prussian Blue type, derived from hexacyanometalate nature of the Schiff base, the metal ion and the n) ions [M(CN)6] and simple transition metal ions, countercation etc., e.g., the discrete heptanuclear exhibit spontaneous magnetization at TC as high as complex [Cr{(CN)Mn(salen Æ H2O)}6][Cr(CN)6] Æ 6H2O 376 K, and interesting optoelectronic and magnetoop- [salen ¼ N,N¢-ethylenebis(salicylideneiminato)dianion] tical properties [6–10]. However, magneto-structural [17], the 1D chain complex [NEt4]2{Mn(acacen)} correlation of these high TC or TN compounds remains [Fe(CN)6] [acacen ¼ N,N¢-ethylenebis(acetylacetony- unclear because of the difficulty in obtaining single lideneaminato)dianion] [18], 2D network complexes crystals. Furthermore, the face-centred cubic structures [{Mn(saltmen)}4{Fe(CN)6}]ClO4 Æ H2O [saltmen ¼ N, (based on powder XRD results) usually possess low or N¢-(1,1,2,2-tetramethylethylene)bis(salicylideneiminato) no magnetic anisotropy. To overcome these problems, a dianion] [19] and [{Fe(salen)}3 {Fe(CN)6}(MeOH)2] Æ wide variety of hybrid Prussian Blue complexes assem- 3H2O [20]. They exhibit the ferromagnetic or antiferro- m) bled from cyanometalate building blocks [M(CN)n] magnetic interaction between adjacent paramagnetic (M ¼ Fe, Cr, Co, Mn, Mo and W etc.) and coordin- centers through the cyanide bridge. Recently, we have atively unsaturated transition metal complexes have prepared two new cyano-bridged coordination III II III polymers, [Fe (salpn)]2[Fe (CN)5NO] (1) and [Fe - II * Author for correspondence (salpn)]2[Ni (CN)4] (2) [salpn ¼ N,N¢-1,2-propylenebis 101 (salicylideneiminato) dianion], using the Schiff base Table 1. Crystallographic data for (1) and (2) complex cation [Fe(salpn)]+ as a template. Here we (1) (2) report the syntheses, structures and magnetic properties of the two 2D assemblies with neutral layers. Formula C39H32Fe3N10O5 C38H32Fe2N8NiO4 Formula weight 888.30 835.13 Crystal system Tetragonal Tetragonal Space group P 4/ncc P 4/ncc Experimental a(A˚ ) 14.3982 (1) 14.250 (2) b (A˚ ) 14.3982 (1) 14.250 (2) Physical measurements c (A˚ ) 18.3434 (1) 18.322 (4) V (A˚ 3) 3802.74(4) 3720.8 (11) Z44 Elemental analyses for C, H and N were performed with )3 Dc (g cm ) 1.552 1.491 a Perkin-Elmer 240C analyzer. Fe and Ni analyses were l (mm)1) 1.188 1.322 made on a Jarrell-Ash 1100 + 2000 inductively coupled Crystal size (mm3) 0.40 · 0.375 · 0.20 0.40 · 0.375 · 0.20 plasma quantometer. I.r. spectra were recorded on a h range ( ) 2.00–25.97 2.22–25.97 Nicolet FT-170SX spectrometer with KBr pellets in the Reflections measured 3568 1357 4000–400 cm)1 region. Magnetic susceptibilities on Independent reflections 1841(Rint = 0.0969) 1355 (Rint = 0.0227) Final R indices R = 0.0698 R = 0.0571 crystalline samples were measured with a Quantum 1 1 [I >2r(I)] wR2 = 0.1474 wR2 = 0.1543 Design MPMS-5 SQUID susceptometer under an ap- Goodness-of-fit 0.931 0.962 plied magnetic field of 10 kOe in the 5–300 K range. Diamagnetic corrections were made using Pascal’s constants. Effective magnetic moments were calculated X-ray crystallography 1/2 using the equation leff ¼ 2.828(vM · T) , where vM is the magnetic susceptibility per formula unit. Diffraction data were collected at 293(2) K on Enraf- Nonius CAD4 and Rigaku AFC5R diffractometers for Syntheses (1) and (2), respectively, using graphite-monochromat- ˚ ed MoKa radiation (k ¼ 0.71073 A)withthex)2h scan All chemicals and solvents used for the synthesis were mode. The unit cell parameters were obtained by a least- reagent grade. The quadridentate Schiff base ligand squares refinement of the setting angles of 25 reflections H2salpn was prepared by mixing salicylaldehyde and with 11.92 < h < 13.90 for (1), and of 20 reflections 1,2-diaminopropane in a 2:1 molar ratio in MeOH with 15.60 < h < 19.62 for (2). The structures were according to the literature [21, 22]. [Fe(salpn)NO3] was solved by direct methods and refined by full matrix 2 prepared by mixing Fe(NO3)3 Æ 9H2O, H2salpn and least-squares techniques based on F . All non-hydrogen LiOH Æ H2O in a 1:1:1.5 molar ratio in MeOH according atoms were refined anisotropically and the sites of to the method reported previously [23]. hydrogen atoms were placed by the geometry. The unweighted and weighted agreement factors of the ) 2 [Fe(salpn)]2 [Fe(CN)5NO] (1) forms R1 ¼ S||F0| |Fc||/S|F0| and wR2 ¼ [S[w(F0 2 2 2 2 1/2 Well-shaped black crystals of (1) were obtained by slow Fc ) ]/S[w(F0 ) ]] were used. The weighting schemes 3 2 2 2 diffusion of a dark brown MeOH solution (15 cm )of are w ¼ 1/[r (F0 ) + (0.0805P) + 0.0000P] (1) and 1/ 2 2 2 2 [Fe(salpn)NO3] (0.15 mmol) and an aqueous solution [r (F0 )+(0.0976P) + 0.0000P] (2), where P ¼ (F0 + 3 2 (15 cm )ofNa2[Fe(CN)5NO] Æ 2H2O (0.15 mmol) 2Fc )/3. All computations were carried out using the through a U-tube containing silica gel at room temper- SHELXTL programs. The crystallographic data are ature. The resulting crystals were collected, washed with summarized in Table 1. H2O and MeOH respectively, and dried in air. (Found: C, 52.2; H, 3.75; N, 16.1; Fe, 19. C39H32Fe3N10O5 calcd.: C, 52.7; H, 3.6; N, 15.8; Fe, 18.9%.) I.r. mmax Results and discussion (cm)1): 2161(s), 1925(vs), 1629(vs), 1596(m), 1548(m), 1468(w), 1446(m), 1395(w), 1322(w), 1293(vs), 1149(w), Spectroscopic studies 900(m), 800(m), 768(s), 615(m). Relevant i.r. spectral data for complexes (1) and (2) are [Fe(salpn)]2[Ni(CN)4] (2) given in the Experimental section. The formation of The complex was prepared as black single crystals in a cyanide bridges in both complexes is evidenced by the way similar to that of complex (1), except for the use of m(CBN) stretching bands in the 2000–2200 cm)1 region. )1 K2[Ni(CN)4] Æ H2O (0.15 mmol) instead of Na2[Fe(CN)5- Complex (1) shows a sharp band at 2161 cm , which NO] Æ 2H2O. (Found: C, 55.1; H, 3.6; N, 13.3; Fe, 13.5; can be attributed to the intermetallic bridging m(CB N), Ni, 7.1. C38H32Fe2N8NiO4 calcd.: C, 54.65; H, 3.9; N, as observed for other cyano-bridged complexes contain- )1 13.4; Fe, 13.4; Ni, 7.0%.) I.r. mmax (cm ): 2155(s), ing nitroprusside. The result also suggests that nearly all 2) 2133(s), 1628(vs), 1596(s), 1544(s), 1469(m), 1445(s), cyanide groups in [Fe(CN)5NO] are involved in 1394(m), 1326(m), 1298(s), 1199(m), 1148(m), 903(m), coordination. A very strong band at 1925 cm)1 for (1) 802(m), 761(s), 615(m), 449(m). is reasonably assigned to the NO stretching vibration, 102
revised diagram
original diagram
Fig. 2. Projection along the c-axis for complex (1), showing a 2D layer structure comprising of pillow-like octanuclear [AFe(II)ACNA
Fe(III)ANCA]4 units.
Table 2. Selected bond lengths (A˚ ) and angles ( ) for (1)
Bond lengths Fe(1)AO(1) 1.898(6) Fe(1)AN(1) 2.111(7) Fe(1)AN(11) 2.175(5) Fe(2)AN(2) 1.64(1) Fe(2)AC(12) 1.77(2) Fe(2)AC(11) 1.930(6) O(1)AC(1) 1.29(1) O(2)AN(2) 1.16(2) N(11)AC(11) 1.137(7) N(12)AC(12) 1.19(2) Bond angles O(1)#1AFe(1)AO(1) 108.1(3) O(1)AFe(1)AN(1)#1 164.6(3) O(1)AFe(1)AN(1) 87.2(3) N(1)#1AFe(1)AN(1) 77.4(5) O(1)#1AFe(1)AN(11) 93.5(2) O(1)AFe(1)AN(11) 90.5(2) N(1)#1AFe(1)AN(11) 85.7(2) N(1)AFe(1)AN(11) 88.9(2) N(11)AFe(1)AN(11)#1 173.1(3) N(11)AC(11)AFe(2) 178.0(7) Fig. 1. ORTEP plot of complex (1). C(12)AFe(2)AC(11) 85.7(3) N(2)AFe(2)AC(11) 94.3(3) C(11)AFe(2)AC(11)#2 171.5(5) C(11)AFe(2)AC(11)#3 89.68(4) C(1)AO(1)AFe(1) 130.4(5) C(7)AN(1)AFe(1) 123.4(6) thus implying that the FeANAO bond is linear [24]. C(8)AN(1)AFe(1) 113.2(7) C(11)AN(11)AFe(1) 164.5(6) Complex (2) shows two strong m(CBN) bands at 2155 )1 Symmetry transformations used to generate equivalent atoms: (#1) and 2133 cm , The shift of m(CBN) to higher wave- ) ) ) ) ) ) )1 y, x, z + 1/2; (#2) x + 1/2, y + 1/2,z; (#3) y, x + 1/2, z and numbers relative to that of K2[Ni(CN)4] (2128 cm ) (#4) )y + 1/2, x, z. [25] suggests the formation of CN) bridges. That m(CBN) of bridging CN) shifts to a higher frequency ) + compared with that of terminal CN is largely attributed each [Fe(salpn)] cation is linked to two [Fe(CN)5- to kinematic coupling whereby the motion of bridging NO]2) ions in trans positions, which results in a 2D CN) is constrained by the second metal center [26]. neutral layered structure consisting of pillow-like octa- II III nuclear [AFe ACNAFe ANCA]4 units. The iron(III) Crystal structures ion in the [Fe(salpn)]+ unit assumes a slightly distorted octahedral coordination geometry in which the equato- An ORTEP diagram of [Fe(salpn)]2 [Fe(CN)5NO] (1) rial sites are occupied by N2O2 donor atoms of the with the atom numbering scheme is shown in Figure 1. quadridentate Schiff-base ligand salpn with FeIIIAN The projection along the c-axis is given in Figure 2. The and FeIIIAO distances of 2.111(7) and 1.898(6) A˚ , selected bond distances and angles are listed in Table 2. respectively; and the axial positions are occupied by II ) III The molecular structure consists of one [Fe (CN)5- two nitrogen atoms from CN groups with Fe AN NO]2) anion and two [FeIII(salpn)]+ cations. Each distance of 2.175(5) A˚ and FeIIIANBC angle of 2) 2) [Fe(CN)5NO] anion coordinates with four [Fe(sal- 164.5(6) . As usual, the [Fe(CN)5NO] fragment ex- pn)]+ cations via four equatorial CBN groups, whereas hibits a distorted octahedral structure. The bond angle 103
Table 3. Selected bond lengths (A˚ ) and angles ( ) for (2)
Bond lengths NiAC(10) 1.867(6) FeAO 1.877(6) FeAN(1) 2.109(7) FeAN(2) 2.178(5) N(2)AC(10) 1.128(8) N(1)AC(7) 1.21(1) Bond angles C(10)#2ANiAC(10) 90 C(10)#3ANiAC(10) 179.6(5) OAFeAO#4 106.4(4) OAFeAN(1)#4 165.8(3) OAFeAN(1) 87.8(3) N(1)#4AFeAN(1) 78.0(5) OAFeAN(2)#4 91.2(2) N(1)AFeAN(2)#4 86.5(3) OAFeAN(2) 93.2(2) N(1)AFeAN(2) 87.8(3) N(2)#4AFeAN(2) 172.6(3) C(1)AOAFe 130.2(5) C(7)AN(1)AFe 125.5(6) C(8)AN(1)AFe 112.1(7) C(10)AN(2)AFe 167.0(6) N(2)AC(10)ANi 178.4(7)
Symmetry transformations used to generate equivalent atoms: (#1) y,)x + 1/2,z; (#2) )y + 1/2,x,z; (#3) )x + 1/2,)y + 1/2,z and (#4) y)1/2,x + 1/2,)z + 1/2.
adjacent trans-[Fe(salpn)]+ cations through four cyano nitrogen atoms with a FeAN distance of 2.178(5) A˚ and Fig. 3. ORTEP plot of complex (2). FeANBC angle of 167.0(6) . The coordination geome- try of the iron(III) ion in the [Fe(salpn)]+ subunit is similar with that of (1). The NiII FeIII and ) of FeIIACBN is 178.0(7) for the bridging CN group. FeIII FeIII separations along the ANiIIACBNAFeIIIA The terminal CN) and NO ligands are co-linear as they linkage are 5.135 and 10.244 A˚ , respectively. The both lie on the twofold axis that passes through iron- nearest intralayer and interlayer FeIII FeIII separations (II). The FeIIACN and CBN bond distances for through space are 7.244 and 9.345 A˚ , respectively. bridging CN) are 1.930(6) and 1.137(7) A˚ , respectively; It should be noted that in complexes (1) and (2), the whereas those for the terminal CN) are 1.77(2) and [Fe(salpn)]+ fragment is bound by two equally strong p- 1.19(2) A˚ , which is accordance with that the antibond- bonding CN) groups, which is different from those ) + 3) ing electrons of CN are involved in coordination. The observed in the 2D [M(salen-substituted)] /[Fe(CN)6] FeIIANO and NAO bond distances are 1.64(1) and adducts [19, 20, 36]. In addition, the interlayer distances 1.16(2) A˚ , respectively. All of these bond distances are of ca. 9.17 A˚ for (1) and 9.34 A˚ for (2) are much comparable with those observed in other nitroprussides shorter than those of above adducts (13.10–16.57 A˚ ), [27–33]. The C(11)AFeIIANO angle (94.3 ) is greater due to the lack of countercation as spacer between two than 90 , whereas the C(11)AFeIIAC(12) angle (85.7 )is adjacent layers in present compounds. The salpn ligands less than 90 . The greater electronegativity of the in (1) and (2) have similar bonding parameters, which nitrosyl group with respect to the cyanide groups [34, are comparable to those in relative complexes. 35] causes deformation away from the nitrosyl end of the octahedral geometry. As shown in Figure 2, Magnetic properties the CN) ligands bridge iron(II) and iron(III) centers to give a wave-like chain. The iron(II) iron(III) and The cryomagnetic properties of complexes (1) and (2) iron(III) iron(III) separations within the chain are are shown in Figures 4 and 5, respectively, in the forms ˚ 5.188 and 10.182 A, respectively. The nearest intralayer of plots of vM and leff versus T. and interlayer iron(III) iron(III) separations through space are 7.337 and 9.172 A˚ , respectively. Complex (1) III II The labeled ORTEP plot of [Fe(salpn)]2[Ni(CN)4] (2) The leff per Fe 2Fe unit at room temperature, 8.36 lB, is shown in Figure 3. Complex (2) is isomorphous with is consistent with the spin-only value of 8.37 lB, which is (1), and the selected bond distances and angles are expected for the magnetically dilute system consisting of listed in Table 3. The molecular structure consists of one two high spin iron(III) ions (S ¼ 5/2) and one low spin 2) + [Ni(CN)4] anion and two Fe(salpn) cations. The iron(II) ion (S ¼ 0), where the spin-only value was II III anion and cation are linked by Ni ACNAFe assem- calculated by assuming gFe ¼ 2.00. Lowering the tem- blies to form a 2D neutral layered structure consisting of perature, the leff value almost remains constant until II III pillow-like octanuclear [ANi ACNAFe ANCA]4 55 K, then decreases gradually in the 55–16 K range, and 2) units. As usual, the [Ni(CN)4] moiety exhibits a square finally decreases sharply to 7.6 lB at 5 K. The 1/vM versus planar structure, in which the Ni(II) ion is located on a T plot obeys the Curie–Weiss law vM ¼ C/(T)h) with ) fourfold axis and coordinated by four CN ligands with a negative Weiss constant h ¼ )1.0 K. These results NiAC bond lengths of 1.867(6) A˚ and NiACBN angles indicate the existence of a weak antiferromagnetic 2) 2) of 178.4(7) . Each [Ni(CN)4] anion coordinates to four interaction. As [Fe(CN)5NO] is diamagnetic, the 104
1.6 9.0
1.4
1.2 8.5 -1 1.0 B µ 0.8 eff 8.0 / /emu mol µ M
χ 0.6
0.4 7.5 0.2
0.0 7.0 0 50 100 150 200 250 300 T/K
Fig. 4. The temperature-dependence of magnetic susceptibility vM(jjj) and the effective magnetic moment leff (sss). The solid line is the calculated curve discussed in the text.
exchange interaction between iron(II)–iron(III) through where Jt, Jc and J¢ stand for the exchange integrals III II the cyanide bridging ligand is negligible. Based on the between two SFe (S ¼ 5/2) spins within the Fe2 Fe crystal structure, two exchange pathways are possible; trimer, between the St effective spins of trimers and one is the intralayer interaction between iron(III) ions between the chains, respectively, and were treated as 2) through the diamagnetic [Fe(CN)5NO] units and the equivalent. The symbols N, g, b and k have their usual other is the interlayer interaction through space. Consid- meanings. By allowing the g and J values to vary, we ering that the shortest iron(III)–iron(III) separation obtained the best fit to the experimental data with ˚ ) )1 between the layers (9.172 A) is longer than that within parameters Jt ¼ Jc ¼ J¢ ¼ 0.017 cm , g ¼ 2.02P and ˚ )6 each layer (7.337 A), the intralayer interaction is domi- the disagreement factor R ¼ 7.9 · 10 [R ¼ (vobs) 2 2 nant and the interlayer interaction is negligible. Thus, the vcalc) /vobs]. As shown in Figure 4, the fit may be susceptibility can be expressed [37] by Equations (1)–(4). considered to be good. The results (Jt ¼ Jc ¼ J¢ <0) show the presence of a weak antiferromagnetic interac- 2Ng2b2 A III v ¼ ; ð1Þ tion between the nearest Fe ions within each sheet t 3kT B through the ANCAFeIIACNA bridges. where Complex (2) A ¼ 330 expð30J =kT Þþ180 expð20J =kT Þ t t Complex (2) has similar magnetic behavior to that of þ 84 expð12Jt=kT Þþ30 expð6Jt=kT Þ III II (1). The leff per Fe2 Ni unit at room temperature, þ 6 expð2Jt=kT Þ; 8.0 lB, is slightly smaller than the spin-only value of 8.37 lB expected for the magnetically dilute high spin B ¼ 11 expð30Jt=kT Þþ9 expð20Jt=kT Þ iron(III) ions [(SFe,SNi,SFe) ¼ (5/2, 0, 5/2), where the spin-only value was calculated by assuming g ¼ 2.00. þ 7 expð12Jt=kT Þþ5 expð6Jt=kT Þ Fe On lowering the temperature, the l value almost 3 exp 2J =kT 1: eff þ ð t Þþ remains constant until 34 K, then decreases gradually in the 32–12 K range, and finally decreases sharply with 2 2 Ng b further decreasing temperature to 7.3 l at 5 K. The vt ¼ StðSt þ 1Þ; ð2Þ B 3kT magnetic susceptibility obeys the Curie–Weiss law with a negative Weiss constant h ¼ )1.1 K. These results Ng2b2 ð1 þ uÞ v ¼ StðSt þ 1Þ; ð3Þ indicate the existence of a weak antiferromagnetic chain 3kT ð1 uÞ 2) interaction. As [Ni(CN)4] is diamagnetic, the ex- change interaction between nickel(II)–iron(III) through where the cyanide bridging ligand is negligible. However, the coupling between two adjacent iron(III) ions could occur u ¼ coth½JcStðSt þ 1Þ=kT kT =JcStðSt þ 1Þ; 2) through the [Ni(CN)4] group. Similar to complex (1), the susceptibility data for (2) can be approximated by vchain Equations (1)–(4) with the best fit parameters v ¼ ; where z ¼ 2; ð4Þ ) ) M 0 2 2 ) 1 6 1 vchainð2zJ =Ng b Þ Jt ¼ Jc ¼ J¢ ¼ 0.02 cm , g ¼ 1.95 and R ¼ 4.4 · 10 105
8.50 1.4
1.2 8.25
-1 1.0 8.00 B
0.8 µ eff 7.75 / /emu mol µ
M 0.6 χ
0.4 7.50
0.2 7.25
0.0 7.00 0 50 100 150 200 250 300 T/K
Fig. 5. The temperature-dependence of magnetic susceptibility vM(jjj) and the effective magnetic moment leff (sss) for (2). The solid line represents the fit discussed in the text.
(Figure 5). The results show the presence of weak 5. A.H. Yuan, J.Z. Zou, B.L. Li, Z.G. Zha, C.Y. Duan, Y.J. Liu, Z. intramolecular FeIII FeIII antiferromagnetic interac- Xu and S. Keizer, Chem. Commun., 1297 (2000). A A IIA A 6. T. Mallah, S. Thiebaut, M. Verdaguer and P. Veillet, Science, 262, tions through the diamagnetic NC Ni CN path- 1554 (1993). ways. 7. W.R. Ently and G.S. Girolani, Science, 268, 397 (1995). It is observed that two paramagnetic centers usually 8. O. Kahn, Nature, 378, 667 (1995). give rise to weak antiferromagnetic interaction when 9. O. Sato, T. Iyoda, A. Fujishima and K. Hashimoto, Science, 272, 2) 2) 704 (1996). bridged by the [Fe(CN)5NO] [27–30] or [Ni(CN)4] 10. S.M. Holmes and G.S. Girolami, J. Am. Chem. Soc., 121, 5593 group [38–39], which can be rationalized by the long (1999). distance between paramagnetic centers. However, to our 11. E. Colacio, M. Ghazi, H. Stoeckli-Evans, F. Lloret, J.M. Moreno knowledge, the antiferromagnetic mechanisms for and C. Perez, Inorg. Chem., 40, 4876 (2001). 2) 2) [Fe(CN)5NO] and [Ni(CN)4] are still unclear, and 12. H.Z. Kou, J.K. Tang, D.Z. Liao, S. Gao, P. Cheng, Z.H. Jiang, more works need to be done to clarify the exchange S.P. Yan, G.L. Wang, B. Chansou and J.P. Tuchagues, Inorg. Chem., 40, 4839 (2001). mechanism. 13. J. Larionova, M. Gross, M. Pilkington, H. Andres, H. Stoeckli- Evans, H.U. Gudel and S. Decurtins, Angew. Chem. Int. Ed., 39, 1605 (2000). Supplementary data 14. M. Ohba, N. Usuki, N. Fukita and H. Okawa, Angew. Chem. Int. Ed., 38, 1795 (1999). 15. Z.J. Zhong, H. Seino, Y. Mizobe, M. Hidai, A. Fujishima, S. Supplementary data are available from the Cambridge Ohkoshi and K. Hashimoto, J. Am. Chem. Soc., 122, 2952 Crystallographic Data Center, 12 Union Road, Cam- (2000). bridge, CB2 1EZ, UK on request quoting the deposition 16. A. Marvilliers, S. Parsons, E. Riviere, J.P. Audiere, M. Kurmoo numbers 193646 and 193647. and T. Mallah, Eur. J. Inorg. Chem., 1287 (2001). 17. X.P. Shen, B.L. Li, J.Z. Zou, Z. Xu, Y.P. Yu and S.X. Liu, Transition Met. Chem., 27, 372 (2002). 18. N. Re, E. Gallo, C. Floriani, H. Miyasaka and N. Matsumoto, Acknowledgments Inorg. Chem., 35, 6004 (1996). 19. H. Miyasaka, N. Matsumoto, H. Okawa, N. Re, E. Gallo and C. Floriani, J. Am. Chem. Soc., 118, 981 (1996). This work was supported by the Natural Science 20. N. Re, R. Crescenzi, C. Floriani, H. Miyasaka and N. Matsumoto, Foundation of the Bureau of Education of Jiangsu Inorg. Chem., 37, 2717 (1998). Province (No. 01KJB150010). 21. P.J. McCarthy, R.J. Hovey, K. Ueno and A.E. Martell, J.Am. Chem. Soc., 77, 5820 (1955). 22. P. Pfeifer, T. Hesse, H. Pfitzner, W. Scholl and H. Thielert, J. Prakt. Chem., 149, 217 (1937). References 23. N. Matsumoto, N. Takemoto, A. Ohyoshi and H. Okawa, Bull. Chem. Soc. Jpn., 61, 2984 (1988). 1. M. Ohba and H. Okawa, Coord. Chem. Rev., 198, 313 (2000). 24. P.N. Hawker and M.V. Twigg, in S.G. Wilkinson, R. Gillard and 2. M. Verdaguer, A. Bleuzen, V. Marvaud, J. Vaissermann, M. J.A. McCleverty (Eds), Comprehensive Coordination Chemistry, Seuleiman, C. Desplanches, A. Scuiller, C. Train, R. Garde, G. vol. 4, Pergamon, Oxford, 1989, p. 1187. Gelly, C. Lomenech, I. Rosenman, P. Veillet, C. Cartier and F. 25. K. Nakamoto, Infrared and Raman Spectra of Inorganic and Villain, Coord. Chem. Rev., 190–192, 1023 (1999). Coordination Compound, 3rd edit., Wiley, New York, 1978, p. 259. 3. W.P. Fehlhammer and M. Fritz, Chem. Rev., 93, 1243 (1993). 26. S.Z. Zhan, D. Guo, X.Y. Zhang, C.X. Du, Y. Zhu and R.N. Yang, 4. K.R. Dunbar and R.A. Heintz, Prog. Inorg. Chem., 45, 283 (1997). Inorg. Chim. Acta, 298, 57 (2000). 106
27. Z.N. Chen, J.L. Wang, J. Qiu, F.M. Miao and W.X. Tang, Inorg. 33. J. Ribas, J.M. Julia, X. Aolans, M. Font-Altaba, A. Isalgue, X. Chem., 34, 2255 (1995). Tejada, Transition Met. Chem., 9, 57 (1984). 28. H.L. Shyu, H.H. Wei and Y. Wang, Inorg. Chim. Acta, 258,81 34. J.E. Huheey, J. Phys. Chem., 69, 3284 ( 1965). (1997). 35. J.E. Huheey, J. Phys. Chem., 70, 2086 (1966). 29. H.Z. Kou, H.M. Wang, D.Z. Liao, P. Cheng, Z.H. Jiang, S.P. 36. H. Miyasaka, N. Matsumoto, N. Re, E. Gallo and C. Floriani, Yan, X.Y. Huang and G.L. Wang, Aust. J. Chem., 51, 661 Inorg. Chem., 36, 670 (1997). (1998). 37. H.Z. Kou, W.M. Bu, D.Z. Liao, Z.H. Jiang, S.P. Yan, Y.G. Fan 30. J.H. Zou, X.Y. Xu, Z. Xu, X.Z. You, X.Y. Huang, W.L. Zhang, and G.L. Wang, J. Chem. Soc., Dalton Trans., 4161 (1998). X.P. Shen and Y.P. Yu, J. Coord. Chem., 43, 273 (1998). 38. Z. Smekal, I. Cisarova and J. Mrozinski, Polyhedron, 20, 3301 31. N. Mondal, M.K. Saha, S. Mitra, V. Gramlich and M.S.E. Fallah, (2001). Polyhedron, 19, 1935 (2000). 39. A.H. Yuan, X.P. Shen, Q.J. Wu, Z.X. Huang and Z. Xu, J. Coord. 32. S. Zhan, X. Chen, A. Vij, D. Guo and Q. Meng, Inorg. Chim. Acta, Chem., 55, 411 (2002). 292, 157 (1999). TMCH 5688