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New Selenolato-Bridged Clusters of Iron and Nickel; the Structures of [Fe12(SePh)24] and [Na2(POPh3)6][Ni20Se12(SeMe)10].

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(51 a) E E. Havinpa. 1. Roite. E. W. Meijer, W. Ten Hoeve. H. Wynberg. Synih.
Mri 1991. 4 / , 473-478; b) D. M. de Leeuw. ihid 1993, -57.3597-3602
[6] a) D. Fichou. H. X u , G. Horowitz. F. Garnier. S M h . M e / . 1991. 41.463-469:
b) P. Riuerle. .-ldv. M a w . 1992.4. 102-107: c) J. Guay, A. Diaz. R. Wu. J. M.
Tour. J. Ani. (%nn.Soc. 1993, 115. 1869-1874.
(71 F. Garnier. A Yaasar, R Hajlaoui, G. Horowitz, F. Deloffre. B. Servet. S. Ries.
P. Alnot. J h i . ( ' / i n n . Soc. 1993. 115. 8716-8721.
[XI B. Xu. D. Fichou. G . Horowitz, F. Garnier, A d v . Muter. 1991, 3. 150-153.
[9] P. Oatoja, S. (iuerri. S. Rossini, M Servidori. C. Taaliani. R. Zamboni, Swrh.
M P ~1993.
.
51. 447 451.
[lo] E Lacax, K CJvdal. P. Bodii. J. Garbarz. W. R. Salaneck. M . Schott. J Po/wn.
S<i Purr 5 -P{J/I.I?I.
Phi,.s. 1993. 3/.111-114.
( I l l H Chitng. A. Bard. Liingnitrir 1991. 7. 1143-1153.
[I21 S. J. Karnrara. M. Zagorska, B. Krische. S. Soderholm. Phys. Scr. 1991. 44.
117 115.
[I31 0 . Riihme. C.. Ziegler. W Gopel. A h Muter. 1994. 6. 587-589.
(141 a ) W. ten Hoeve. H. Wqnberg. E. E. Havinga, E. W. Meijer, J. A m . C h m . Soc.
1991.113. SX87 5x89: b) A. Yassar. D. Delabouglise. M. Hmyene. B. Nessak.
G . Horowit7. F. Garnier. A h . . M a w . 1992, 4 . 490- 494.
[IS] M. Sato. M. Hiroi. C h w . Left. 1994, 985-988.
[I61 P Biiucrle. F. Pfau, H. Schlupp. F. Wurthner, K.-U. Gaudl, M. Balparda Caro.
P. Fixher. .I Chew. Soc. Perkin Trans. 2 1993, 489-494
[I71 a ) T. Kauffm;inn. ilngnz.. Chem. 1974, 86. 321 -335; Angew. Chem. I n / Ed.
E q I . 1974. 1.1. 291 305, h) J. Kagan. S. K. Arora. Hetemrycles 1983. 20.
1937 1940
[ I X ] R. M . Kellopg, A. P. Schaap, H. Wynberg. J Org. Chern. 1969. 34. 343-346.
[I91 T. Kaulfniann, H. Lexy. Chem. Eer. 1981. f14,3674-3683.
[20] Thc unsuhbtituted quaterthiophene has a melting point of 215-216'C; J.
Nakayiima. T Konishi. S. Murabayashi. M. Hoshino. Hererocycli~.~
1987. 26.
1793 17Y6.
[21] P. Hituerle. U. Segelbacher. K:U. Gaudl. D. Huttenlocher. M. Mehring,
A n p ' i i . ('Irwn. 1993. 105. 125-127; Angrw. Chem. Int. Ed. Engl. 1993, 32.
76 18.
1221 a ) M. G Hill. K. R. Mann, L. L. Miller, J.-F. Penneau, J Am. Chem. Soc. 1992,
/14. 272K 2730: b) P BBuerle, U. Segelbacher, A. Maier, M. Mehring. ihid
1993. lli. 10217 10223.
[23) Polymerization of 3-dodecyl-2,2'-bithiophene[16], which corresponds to half
of quaterthiophene 1. leads to a polymer that also has one solubilizing group
per two thiophene unita. The polymer has an oxidation potential of
E,,&= 0.35 V v s FcjFc'.
[24] J. P. Rabe, S. Buchholz, L. Askadskaya. Phys. Scr. 1993, T4Y. 260-263.
[25] A. Stabel. J. P. Rabe. Synrh. Mer.. 1994, 67, 47-53.
[26] J. P. Rabe. M. Sano, D. Batchelder. A. A. Kalatchev, J Micrmc. (0.XfordJ
1988, 152, 573 578.
PhSeSiMe, [Eq. (a)]. In THF and toluene at room temperature.
only amorphous powder is obtained, some of which is py-
rophoric. In contrast, 1 crystallizes in the form of shiny black
needles within 12 h when a suspension of FeCI, and PPh, in
dichloroethane is carefully covered with a layer of PhSeSiMe,.
Compound 1 decomposes readily on warming in organic solvents releasing elemental selenium. The IR spectrum of 1 contains the characteristic bands of the PhSe group, but further
structural information cannot be extracted. An X-ray crystal
structure analysis was carried out on 1 to determine the molecular structure.[" Depending on the conditions of crystallization,
crystals containing varying amounts of dichloroethane are
formed. 1 .4C,H,CI, crystallizes in the tetragonal space group
P42,c. and 1.5C,H4CI, in the orthorhombic space group
Pnzmn; however, this has practically no influence on the bonding parameters of 1.
Figure 1 shows that a cyclic Fe,, cluster is present in 1 which
has 4 symmetry in the tetragonal cell. Each Fe atom is surrounded by four Se atoms of the p,-SePh ligands in a distorted tetrahedral fashion. As a result, edge-sharing Se, tetrahedra connect
to form a ring. The Fe atoms are located in the centers of the Se,
tetrahedra (Se . . Se 360-428 pm). The principle of bridging
5,
New Selenolato-Bridged Clusters of Iron and
Nickel; the Structures of [Fe, 2(SePh),,] and
" ~ * ~ ~ ~ ~ ~ , ~ , J " ~ , o ~ ~ , * ~ ~ ~ ~ ~ ~ l o l * *
Dieter Fenske* and Andreas Fischer
Dedicutred lo Projessor Dr. Gerhurd Fritz
on the o c i u ~ i o nof his 75th birthduy
The reactions of phosphane complexes of transition metal
halides with E(SiMe,), (E = S, Se, and Te) lead to a great number
of multinuclear clusters, whose frameworks contain sections from
the structures of binary chalcogenides, which-are surrounded by
a protecting shell of PR, ligands (R = organic group).['] We
have now investigated whether PhSeSiMe, and NaSeMe can
also be used for the synthesis of these types of clusters.
As an example, we found that the Fe,, cluster 1 is formed
almost quantitatively in the reaction of FeCI, with PPh, and
[*] Prof Dr D. Fenske. Dipl.-Chem. A. Fischer
lnstitut fiir Anorganische Chemie der Universitit
Engesserstrasse. Geb.-Nr. 30.45. D-76128 Karlsruhe (Germany)
Telefax: Int. code + (721)661921
[**I
This work was supported by the Deutsche Forschungsgemeinschaft (Sonderforschungsbereich 195) and the Fonds der Chemischen Industrie.
Angrit. ('hmt. Inr Ed. Engl. 1995, 34, No. 3
C
Fig. 1. Top: Ball-and-stick model of 1 (without Ph groups): bottom: polyhedron
model of the edge-hridged Se, tetrahedra (Fe: blue: Se: orange). Selected distances
[ i O . 2 pm]: Sel-Fe2 242.0, Sel-Fe3 244.6. Se2-Fe2 243.5. Se2-Fel 243.6. Se3-Fel
244.8, Se3-Fe3 245.0. Se4-Fe2 243.8, Se4-Fel 246.6. Se5-Fe3 243.4. Se5-Fel 244.8,
Se6-Fe2 243 4, Se6-Fe3 244.1. Se-C 192-197.
VCH Verlagsgese1kchaf~mhH, D-6Y451 Weinheirn, 1Y95
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chalcogen polyhedra is found in the structures of many ternary
chalcogenides. In contrast to 1, vertex-sharing and edge-sharing
E, tetrahedra (E = chalcogen) are observed to form dimeric and
trimeric units, or even infinite chains in these compounds.[31
The shortest Fe-Fe distances in 1 are 286.7-290.1 pm. They
are thus comparable to the distances in [Fe,(SEt),]'- (Fe-Fe:
297.8 pm) and Ba,(Fe,S,), (Fe-Fe: 275.1 -286.8 pm),13,41as
well as those in [Fe3S4(SEt),l3- (Fe-Fe: 271.4 pm), and
[NaZFe,,Se,,l8and [Na,Fe,,S,,]9(Fe-Fe:
272289 pm).L5,61
As in 1, a ring-shaped cluster is also found in [NazFel,S,,]8which is formed by the connection of S, tetrahedra having Fe
atoms at their centers. In addition, two Fe,S units are located at
the center of the cluster. These four Fe atoms carry the
charge 2; the remaining 14 Fe atoms occur as Fe3+ ions.
In contrast to this, 1 contains iron centers only in the formal
oxidation state + 2 (d6 configuration). Preliminary results from
the Mossbauer spectra indicate the presence of Fez+ ions in
tetrahedral environments. Obviously, considerable interactions
between the Fe2+ ions must be considered.['] This is possibly
one explanation for the fact that a magnetic moment of pelf =
1.51 pB/Fe (at 293K) was found. In this context, it must be
mentioned that investigations have already been performed on
ring-shaped iron clusters containing oxygen ligands.[81 The
magnetic properties of [{Fe(OMe),(O,CCH,C1)),,1, a compound with octahedrally coordinated Fe3+ ions bridged by
OMe and 0,CCH2C1 ligands, are well understood.[81Just as in
1, antiferromagnetic coupling between the Fe3' ions is observed
(Fe-Fe: 302.8 pm).[']
A space-tilling model of 1 (Fig. 2) clearly shows that the Fe,,
cluster ring is effectively shielded by the Ph groups bonded to
the Se atoms. The Ph groups are arranged in an alternating
fashion above and below the Fe,, cluster plane. The entire molecule has a diameter of about 12 A.
a reaction that has not yet been clarified. The main products
of the reaction are NiS and as yet unidentified cluster complexes.
Product 2 is an ionic compound consisting of a
[Na,(POPh,)J2+ ion and a ~i,,Se,,(SeMe),,j2- ion. Two Na'
ions are found in the centrosymmetrical cation (Fig. 3), each of
which is coordinated by the 0 atoms of the POPh, ligands in a
+
w
Fig. 3. The structure of the [Na,(POPh,),]z+ ion in 2 (H atoms not shown). Selected distances [&0.9pm] and angles [ & 0.2 ]: N a l - 0 1 227.4, NalB-01 231.5, N a l 0 2 218.4, N a l - 0 3 216.5, Nal ... NalB 333.1, P1-03 147.9, P2-02 150.1. P3-01
149.1; Nal-Ol-P3 126.4 (134.3). 0 2 - N a l - 0 3 115.4. 0 2 - N a l - 0 1 108.3 (120.5). 0 3 N a l - 0 1 110.1 (112.0).
distorted tetrahedral fashion. The oxygen atoms 0 3 and 02,
which are bonded to PI and P2, respectively, are about 10 pm
closer to Nal than 0 1 is ( N a l - 0 1 : 227.4; N a l - 0 2 : 218.4;
Nal-03:216.5 pm). POPh, is obviously necessary for the formation of this cation; it arises possibly from the reaction of
PPh, with the solvent or with oxygen.
A certain structural relationship can be recognized between
the structure of the [Ni2,Se,,(SeMe),,]2- ion with 7 symmetry
(Fig. 4) and that of the (as yet) largest nickel chalcogenide cluster [Ni,,Se,,(PPh,),,] .["I
A pentagonal antiprism of Ni atoms (Nil -Ni5 and atoms at
inverted sites) makes up the central unit in the cluster anion of
Fig. 2. Space-filling model of 1 (Fe: blue; Se: red; C: black; H: white). The Fe
atoms are barely visible.
A further possibility for the synthesis of metal clusters with
bridging chalcogen ligands is the reaction of metal halides with
NaSR.". 6 , lo] For example, the reaction of NiC1, with NaSMe
(in the presence of Me,NCI) leads to the complex (Me,N),[Ni,(p,-S)(p,-SMe),] .[ll] On the other hand, if [NiCl,(PPh,),] is
treated with NaSeMe, black crystals of 2 are obtained in a yield
of about 10% [Eq. (b)]. Cluster 2 is formed as a side product in
9s
[NiCI,(PPh,),]
+ NaSeMe
--t
[Na,(POPh,),][Ni,,Se,,(SeMe),,]
2
308
C
VCH VerlagsgesellschuJfl mbH, D-69451 Weinheim. 1995
(b)
Fig. 4. The structure of the [Ni,,Se,,(SeMe),,12- ion in 2. Selected distances
[+0.3 pm]: Nil-Ni2 248.2. Nil-Ni5 248.2, Ni2-Ni3 246 2, Ni3-Ni4 248.9, Ni4-NiS
245.5, Ni6-Ni7 258.9, Ni7-Ni8 257.1, Ni8-Ni9 254.3, Ni9-Nil0 256.3, Ni6-Nil0
259.8. Sel I-Ni 235.6-239.1, (pc,-Se)-Ni 233.9 -239.0. (p,-Se)-Ni 233.6-238.2.
0570-08331YSJ0303-0308$. 10.00f .25/0
Angew Chem. hi.Ed. Engl. 1995. 34, N o . 3
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2; the Ni-Ni distances (in the pentagonal ring) lie between 245.5
and 248.9 pm. In contrast, the Ni-Ni distances between the
pentagonal layers are on average more than 260 pm, and the
remaining Ni-Ni distances lie between these values. In the anion of 2 ii,-Se (Sell. Sell'), p,-Se (Se6-SelO), and pc,-SeMe
(Sel-Se5) ligands are present. This shows that the cluster is
formed as a result of a complex reaction which takes place
partially by cleavage of the Se-C bonds.
Just as in [Ni,,Se,,(PPh3)to], two p,-Se ligands (Sell) in the
anion of 2 cap the top and bottom Ni, rings. The remaining Se
atoms act as p4 ligands, whereas the SeMe groups are p2 bridging. As a result of this arrangement, one Ni, unit is located over
each triangular face of the pentagonal antiprism. These Ni,
units. together with the p,-Se bridging atom and the Ni atoms
of the triangular face, give rise to octahedra consisting of five Ni
atoms and one Se atom (e.g. N i l , Ni3, Ni4, Ni6, NilO, Se9).
Thus the cluster can be described as a ring made up of facesharing Ni,Se octahedra, in which the Se atoms are arranged in
an alternating fashion above and below the ring planes. The
outer Nil,, ring (Ni6-Nil0 and atoms at inverted sites) is additionally bridged by ten p2-SeMe groups and thus sterically saturated. The Ni atoms Ni6-Nil0 are each coordinated by two
SeMe- and two SeZ- ligands in a distorted tetrahedral fashion.
In contrast, the Ni atoms of the pentagonal antiprism are coordinated by three Se2- ligands.
[Ni,oSei2(SeMe),o]2-contains a Ni:j+ cluster; the Ni atoms
thus have the formal oxidation number 1.6. Mixed-valent states
are well known for nickel. For example, the Ni atoms in
[Ni34Se,2(PPh3)io]have a formal oxidation number of 1.7, and
those in [Ni,S(SC,H,),]- of 1.25.[". 13] A simple description of
the bonding situation in the cluster anion is not possible, as an
assignment of Ni-Ni bonds is only possible when arbitrary
assumptions are made. We have already had similar difficulties
with other chalcogenidonickel cluster complexes.['] This in
mind, it is not surprising that the 18electron rule and topological rules are not complied with.ft4]
~
.
[3]
[4]
[S]
[6]
[7]
[8]
[9]
[lo]
(1 11
[12]
[13]
[I41
E.syrirnentuI Procedure
I : FeCI, (0.16 g. 1 mmol) and PPh, (0.26 g, 1 mmol) were suspended in
dichloroethane (80 mL). Solid undissolved material remained at the bottom of the
red solution. The solution was then carefully covered with a layer of PhSeSiMe,
(1 inL. 4 mrnol). The solution became colorless at the phase boundary, and a white
precipitate was observed. In the course of the following 24 h. the solution turned
first dark green mid then dark brown. Long dark needles of 1 started to grow on the
walls of the reaction vessel along the diffusion boundary. Yield 90%. I n contrast,
when PPh, (0.52 g. 2 mmol) and PhSeSiMe, (1 mL, 4 mmol) were added to FeCI,
(0.24 g. 2 mmol) i n ii heterogeneous reaction, in addition to 1, a pyrophoric residue
was also obtained. which was presumably elemental iron.
2. [Ni<:I,(PPh,)J (4 44 g, 6.7 mmol) and NaSeMe (2.8 g, 23.9 mmol) were suspended in T H F (100 mL) and stirred for several minutes. The suspension turned dark
red. Alter a reaction time of several weeks. a powder was formed containing NaCl
and other diverse products. In addition, triclinic crystals of 2 were obtained in the
form of black loienges.
Received: September 2, 1994 [Z72871E]
German version: Angcn. Chem. 1995, 107, 340
Keywords: clusters . complexes with selenium ligands . iron compounds nickel compounds
stants (ZOOK): u = h =2535.5(12). <'=1391.3(6)pm. 2 = / i=90".
=?
V=
8944.3 x 10" pm3: inversion twin space group f32,c(no. 1 II),k = 2. {t(MoK,1
= 58.4cm-'. 20,,, = 56'. 25294 reflections, ofwhich I0556 with I
2n(/).
anisotropic refinement; R , = 0.082. The phcnyl groups ,ire partially disordered. I-SC,H,CI,' lattice constants (200K). u = 1372 3(9). h = 2542.4(12).
L' = 2578.3(12) pm.
r = /l
= )I = YO',
L' = 8995.5 x 10' pin': sp;ice group
Pmmn (no. 59). 2 = 2. p(MoKJ = 58.7 c m - ' . 20 ",,, = 52 . Y678 reflections. of
which 5638 independent with I > Zn(/), Fe. Se anisotropic. C isotropic. R , =
0.086. R1 = 0.082. 2: lattice constants (200K): u =1348.7(7). h =1596.3(11).
r=1847.5(8)pm, 2 =97.18(4), /1=106.71(4). ;.=103.05(3) L ' = 3 6 3 3 . 5 ~
10"pm': space group Pi (no. 2). Z =I,idMoKJ =79.5 c m - ' . Xi,,.,, = 52 ,
36312 reflections, ofwhich 15851 independent with I > ~ G I IX01
) . parameters
(Ni. Se. P, 0. Na. C anisotropic. the positions of the hydrogen atoms were
calculated). R , = 0.080. R, = 0.076. Further details of the crystal structure
investigation may be obtained from the Fachinformations7entrum Karlsruhe.
D-76344 Eggenstein-Leopoldshafen (Germany) on quoting the depository
number CSD-58 694.
W. Bronger. P. Miiller. J. Lcss Cinnnmn M o . 1984, /0(1. 241; W, Bronger,
A n g r w Chem. 1981, 93. 12; Angeir. C'hem. In[. €d. €ng/. 1981. 31). 52; J. T.
Hoggins, H. Steinfink. Aciu Crwrullogr. Secr. B 1977. 33, 673: J. T Lemley.
J. M. Jenks. J. T. Hoggins. 2. Eliezer, H. Steinlink, J. S o l d Srure Chmi. 1976.
16. 117; H. Y. Hong. H. Steinfink. ibrd. 1972.5.93; J. S. Swnnca. H. Steinfink,
ibid. 1980. 32. 329.
K. S. Hagen, R. H. Holm. Inor,?. Chem. 1984. 23, 418.
K. S. Hagen, A. D. Watson, R . H . Holm, J A m Chem ,Sw 1983, 105. 3905.
J.-F. You. B. S. Snyder, R. H. Holm, J. Am. C/wm. Sor. 1988. 110. 6589; JF
:.
You, R. H. Holm, fnorg. Chem. 1991. 30. 1431: J.-I- You, G. C. Papaefthymiou. R. H. Holm, J. A m Chem. Sot. 1992. 114. 7697.
J. Ensling. Universitit Mainz, personal communication.
D. Gatteschi, A. Caneschi. L. Pardi. R. Sessoli. Scirwcc 1994,265, 1054; K. L.
Taft, S. Lippard, J. '4m. Chem. Sac. 1990. 112. 9629.
J. J. Girerd, G. C. Papaefthymiou, A. D. Watson. E. Gamp. K . S. Hagen. N .
Edelstein. R. B. Frankel. R. H. Holm, J. A m . Chem. Soi. 1984. 106. 5941; S. C.
Lee. R. H. Holm. Aiigeir. Cheni. 1990. 102. 868; AngPw ( ' / ? m i . Inr. .Ed Engl.
1990, 29. 840.
S. Otsuka. M. Kamata. K. Hirotsu, T. Higuchi. J. A m . (%c,m. Soc. 1981. /03,
3011; K . S. Hagen, G. Christou. R. H. Holm. fnorg. Chrm. 1983. 22. 309; G.
Christou. K . S. Hagen, J. K. Bashkin, R. H . Holm, h i d . 1985. 24. 1010: M.
Kriege, G. Henkel. 2. Nulurfursch. B. 1987. 41. 1121
G. Henkel. M. Kriege. K. Matsumoto. J. Chem. So<. Dulion 7rurw. 1988, 657.
D. Fenske. J. Ohmer, J. Hachgenei. Angriv. Chem. 1985. Y7.993: A n g r w Chem.
Ini. Ed. Engl. 1985. 24. 993.
T. Kriiger. B. Krebs. G . Henkel, Angeir. Chem. 1989. 101. 54; Angeii.. Ckcm.
h i . Ed. Enx/. 1989. 28. 61.
B. K. Teo, Inorx. Chem. 1984, 23. 1251; B. K. Teo, G . Longoni. F. R . K.
Chung. hid. 1984, 23. 1257: B. K. Teo, J. Chem. SOL.C h ~ ? iConimun.
.
1983.
1362; D. M. P. Mingos, R. L. Johnston, Slrucc. Bonding iBidin) 1987,6R. 29;
D. M. P. Mingos, Chem. Sor. Rev. 1986, 15. 31 ; J. Chem. Soc. Chem. Commun.
1985. 1352.
Side-Chain Polyrotaxanes with a Tandem
Structure Based on Cyclodextrins and
a Polymethacrylate Main Chain**
Markus Born and Helmut Ritter*
The chemistry of the rotaxanes has moved out of the area of
low molecular weight compounds (Scheme 1, A) in the direction
of polymeric structures, in which the linear "thread" molecules
pass through a number of crown ethers or cyclodextrins.". 21
Recently we extended this group of main-chain polyrotaxanesI3 51 (Scheme 1. B) with a new class of side-chain polyrotaxanes (Scheme 1 , D) based on polymethacrylate, polysulfone,
and polyether ketone main chains.[6-81
~
[I] D. Fenske. J. Ohmer. J. Hachgenei. K . Merzweiler. Anpew Chem 1988, 100.
1300: A n g ~ i i C
. h m . I n r . Ed. EngI. 1988. 27, 1277; H. Krautscheid, D. Fenske.
(i.
Baum, M Semmelmann, Angew. Clwm. 1993. 105, 1365: Angew. Chem. I n [ .
E d EngI. 1993.32. 1302: D . Fenske. H. Krautscheid. ibid. 1990. 102. 1513 and
1990, l Y . 1453; D. Fenske. J. Steck. ihid. 1993, 105,254 and 1993,32. 238; S.
Dehnen. A. Schifer. D. Fenske, R. Ahlrichs, ibid. 1994, 106, 786 and 1994,33,
746.
(21 Ci-ystel structure analyses: Stoe Stadi-IV and Stoe IPDS diffractometers
(Mo,, radiation. empirical absorption correction); data collection and refinement (SHELXS-86. SHELXL-93. SCHAKAL). 1~4C,H,CI,: lattice conAngeic. Clrsni. lni.
Ed. EngI. 1995. 34. N o . 3
0 VCH
[*] Prof. Dr. H. Ritter, M. Born
Fachbereich 9, Organische Chemie
und Makromolekulare Chemie der Universitit
GauSSStrdSSe 20, D-42097 Wuppertal (Germany)
Telefax: Int. code + (202)439-2648
[**I
We thank Dr. C. M. Weisshuhn for recording the NMR spectra and the
Deutsche Forschungsgemeinschaft for financial support
Verlug~gesel/.~cl~ufr
mhH. 0-69451 Weinkeim, 1995
0570-0833~95~0303-0309
$10.00+ ,25;0
309
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nickell, bridge, seph, new, na2, structure, clusters, iron, selenolato, poph3, seme, ni20se12, fe12
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