Formation, Characterization, and Bonding of cis- and trans-[PtCl2{Te(CH2)6}2], cis-trans-[Pt3Cl6{Te(CH2)6}4], and cis-trans-[Pt4Cl8{Te(CH2)6}4]: Experimental and DFT Study.

[PtCl2{Te(CH2)6}2] (1) was synthesized from the cyclic telluroether Te(CH2)6 and cis-[PtCl2(NCPh)2] in dichloromethane at room temperature under the exclusion of light. The crystal structure determination showed that in the solid state, 1 crystallizes as yellow plate-like crystals of the cis-isomer 1cis and the orange-red interwoven needles of 1trans. The crystals could be separated under the microscope. NMR experiments showed that upon dissolution of the crystals of 1cis in CDCl3, it isomerizes and forms a dynamic equilibrium with the trans-isomer 1trans that becomes the predominant species. Small amounts of cis-trans-[Pt3Cl6{Te(CH2)6}4] (2) and cis-trans-[Pt4Cl8{Te(CH2)6}4] (3) were also formed and structurally characterized. Both compounds show rare bridging telluroether ligands and two different platinum coordination environments, one exhibiting a cis-Cl/cis-Te(CH2)6 arrangement and the other a trans-Cl/trans-Te(CH2)6 arrangement. Complex 2 has an open structure with two terminal and two bridging telluroether ligands, whereas complex 3 has a cyclic structure with four Te(CH2)6 bridging ligands. The bonding and formation of the complexes have been discussed through the use of DFT calculations combined with QTAIM analysis. The recrystallization of the mixture of the 1:1 reaction from d6-DMSO afforded [PtCl2{S(O)(CD3)2}{Te(CH2)6}] (4) that could also be characterized both structurally and spectroscopically.

Experimental and computational investigation on the formation pathway of [RuCl2(CO)2(ERR')2] (E = S, Se, Te; R, R' = Me, Ph) from [RuCl2(CO)3]2 and ERR'.

The pathways to the formation of the series of [RuCl2(CO)2(ERR')2] (E = S, Se, Te; R, R' = Me, Ph) complexes from [RuCl2(CO)3]2 and ERR' have been explored experimentally in THF and CH2Cl2, and computationally by PBE0-D3/def2-TZVP calculations. The end-products and some reaction intermediates have been isolated and identified by NMR spectroscopy, and their crystal structures have been determined by X-ray diffraction. The relative stabilities of the [RuCl2(CO)2(ERR')2] isomers follow the order cct > ccc > tcc > ttt ≈ ctc (the terms c/t refer to cis/trans arrangement of the ligands in the order of Cl, CO, and ERR'). The yields were rather similar in both solvents, but the reactions were significantly faster in THF than in CH2Cl2. The highest yields were observed for the telluroether complexes, and the yields decreased with lighter chalcogenoethers. PBE0-D3/def2-TZVP calculations indicated that the reaction path is independent of the nature of the solvent. The substitution of one CO ligand of the intermediate [RuCl2(CO)3(ERR')] by the second ERR' shows the highest activation barrier and is the rate-determining step in all reactions. The observed faster reaction rate in THF than in CH2Cl2 upon reflux can therefore be explained by the higher boiling point of THF. At room temperature the reactions in both solvents proceed equally slowly. When the reaction is carried out in THF, the formation of [RuCl2(CO)3(THF)] is also observed, and the reaction may proceed with the substitution of THF by ERR'. The formation of the THF complex, however, is not necessary for the dissociation of the [RuCl2(CO)3]2. Thermal energy at room temperature is sufficient to cleave one of the bridging Ru-Cl bonds. The intermediate thus formed undergoes a facile reaction with ERR'. This mechanism is viable also in non-coordinating CH2Cl2.

Correction: Tellurium: a maverick among the chalcogens.

Correction for 'Tellurium: a maverick among the chalcogens' by Tristram Chivers and Risto S. Laitinen, Chem. Soc. Rev., 2015, 44, 1725-1739, DOI: 10.1039/C4CS00434E.

Chalcogen-Bonding Interactions in Telluroether Heterocycles [Te(CH2 )m ]n (n=1-4; m=3-7).

Invited for the cover of this issue are the groups of Risto Laitinen at University of Oulu and Wolfgang Weigand at Friedrich Schiller University Jena. The image depicts a picturesque view of the Te⋅⋅⋅Te close contacts forming infinite tubular shafts in 1,9,17,25-Te4 (CH2 )28 . The cover artwork was designed and created by Marko Rodewald. Read the full text of the article at 10.1002/chem.202002510.

Iron-Intercalated Zirconium Diselenide Thin Films from the Low-Pressure Chemical Vapor Deposition of [Fe(η5-C5H4Se)2Zr(η5-C5H5)2]2.

Transition metal chalcogenide thin films of the type Fe x ZrSe2 have applications in electronic devices, but their use is limited by current synthetic techniques. Here, we demonstrate the synthesis and characterization of Fe-intercalated ZrSe2 thin films on quartz substrates using the low-pressure chemical vapor deposition of the single-source precursor [Fe(η5-C5H4Se)2Zr(η5-C5H5)2]2. Powder X-ray diffraction of the film scraping and subsequent Rietveld refinement of the data showed the successful synthesis of the Fe0.14ZrSe2 phase, along with secondary phases of FeSe and ZrO2. Upon intercalation, a small optical band gap enhancement (E g(direct) opt = 1.72 eV) is detected in comparison with that of the host material.

Chalcogen-Bonding Interactions in Telluroether Heterocycles [Te(CH2 )m ]n (n=1-4; m=3-7).

The Te⋅⋅⋅Te secondary bonding interactions (SBIs) in solid cyclic telluroethers were explored by preparing and structurally characterizing a series of [Te(CH2 )m ]n (n=1-4; m=3-7) species. The SBIs in 1,7-Te2 (CH2 )10 , 1,8-Te2 (CH2 )12 , 1,5,9-Te3 (CH2 )9 , 1,8,15-Te3 (CH2 )18 , 1,7,13,19-Te4 (CH2 )20 , 1,8,15,22-Te4 (CH2 )24 and 1,9,17,25-Te4 (CH2 )28 lead to tubular packing of the molecules, as has been observed previously for related thio- and selenoether rings. The nature of the intermolecular interactions was explored by solid-state PBE0-D3/pob-TZVP calculations involving periodic boundary conditions. The molecular packing in 1,7,13,19-Te4 (CH2 )20 , 1,8,15,22-Te4 (CH2 )24 and 1,9,17,25-Te4 (CH2 )28 forms infinite shafts. The electron densities at bond critical points indicate a narrow range of Te⋅⋅⋅Te bond orders of 0.12-0.14. The formation of the shafts can be rationalized by frontier orbital overlap and charge transfer.

Neutral binary chalcogen-nitrogen and ternary S,N,P molecules: new structures, bonding insights and potential applications.

Early theoretical and experimental investigations of inorganic sulfur-nitrogen compounds were dominated by (a) assessments of the purported aromatic character of cyclic, binary S,N molecules and ions, (b) the unpredictable reactions of the fascinating cage compound S4N4, and (c) the unique structure and properties of the conducting polymer (SN)x. In the last few years, in addition to unexpected developments in the chemistry of well-known sulfur nitrides, the emphasis of these studies has changed to include nitrogen-rich species formed under high pressures, as well as the selenium analogues of well-known S,N compounds. Novel applications have been established or predicted for many binary S/Se,N molecules, including their use for fingerprint detection, in optoelectronic devices, as high energy-density compounds or as hydrogen-storage materials. The purpose of this perspective is to evaluate critically these new aspects of the chemistry of neutral, binary chalcogen-nitrogen molecules and to suggest experimental approaches to the synthesis of target compounds. Recently identified ternary S,N,P compounds will also be considered in light of their isoelectronic relationship with binary S,N cations.

Titanocene Selenide Sulfides Revisited: Formation, Stabilities, and NMR Spectroscopic Properties.

[TiCp2S5] (phase A), [TiCp2Se5] (phase F), and five solid solutions of mixed titanocene selenide sulfides [TiCp2SexS5-x] (Cp = C5H5-) with the initial Se:S ranging from 1:4 to 4:1 (phases B⁻E) were prepared by reduction of elemental sulfur or selenium or their mixtures by lithium triethylhydridoborate in thf followed by the treatment with titanocene dichloride [TiCp2Cl2]. Their 77Se and 13C NMR spectra were recorded from the CS2 solution. The definite assignment of the 77Se NMR spectra was based on the PBE0/def2-TZVPP calculations of the 77Se chemical shifts and is supported by 13C NMR spectra of the samples. The following complexes in varying ratios were identified in the CS2 solutions of the phases B⁻E: [TiCp2Se5] (51), [TiCp2Se4S] (41), [TiCp2Se3S2] (31), [TiCp2SSe3S] (36), [TiCp2SSe2S2] (25), [TiCp2SSeS3] (12), and [TiCp2S5] (01). The disorder scheme in the chalcogen atom positions of the phases B⁻E observed upon crystal structure determinations is consistent with the spectral assignment. The enthalpies of formation calculated for all twenty [TiCp2SexS5-x] (x = 0⁻5) at DLPNO-CCSD(T)/CBS level including corrections for core-valence correlation and scalar relativistic, as well as spin-orbit coupling contributions indicated that within a given chemical composition, the isomers of most favourable enthalpy of formation were those, which were observed by 77Se and 13C NMR spectroscopy.

Macrocycles containing 1,1'-ferrocenyldiselenolato ligands on group 4 metallocenes.

Macrocyclic [Fe(η5-C5H4Se)2M(η5-C5H4R)2]2 [M = Ti (1), Zr (2), Hf (3), R = H; and M = Zr (4), Hf (5), R = tBu] were prepared and characterized by 77Se NMR spectroscopy and the crystal structures of 1-3 and 5 were determined by single-crystal X-ray diffraction. The crystal structure of 4 is known and the complex is isomorphous with 5. 1-5 form mutually similar macrocyclic tetranuclear complexes in which the alternating Fe(C5H4Se)2 and M(C5H4R)2 centers are linked by selenium bridges. The thermogravimetric analysis (TGA) of 1-3 under a helium atmosphere indicated that the complexes undergo a two-step decomposition upon heating. The final products were identified using powder X-ray diffraction as FexMSe2, indicating their potential as single-source precursors for functional materials.

Accessing new 2D semiconductors with optical band gap: synthesis of iron-intercalated titanium diselenide thin films via LPCVD.

Fe-doped TiSe2 thin-films were synthesized via low pressure chemical vapor deposition (LPCVD) of a single source precursor: [Fe(η5-C5H4Se)2Ti(η5-C5H5)2]2 (1). Samples were heated at 1000 °C for 1-18 h and cooled to room temperature following two different protocols, which promoted the formation of different phases. The resulting films were analyzed by grazing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and UV/vis spectroscopy. An investigation of the Fe doping limit from a parallel pyrolysis study of Fe x TiSe2 powders produced in situ during LPCVD depositions has shown an increase in the Fe-TiSe2-Fe layer width with Fe at% increase. Powders were analyzed using powder X-ray diffraction (PXRD) involving Rietveld refinement and XPS. UV/vis measurements of the semiconducting thin films show a shift in band gap with iron doping from 0.1 eV (TiSe2) to 1.46 eV (Fe0.46TiSe2).

Fundamental chemistry of binary S,N and ternary S,N,O anions: analogues of sulfur oxides and N,O anions.

Binary S,N anions, e.g., NSN2- and SSNSS-, and related ternary S,N,O anions such as the structural isomers NSO-/SNO- and SSNO- are rarely mentioned in inorganic chemistry textbooks, despite the fact that their salts were synthesised and structurally characterised more than 30 years ago. These fundamentally important species and their conjugate acids, e.g. HNSO and HSNO, have been the focus of numerous investigations in recent years in view of their significance in disciplines as diverse as atmospheric chemistry and cell biology. This Tutorial Review provides a consolidated account of the fundamental chemistry including synthesis, spectroscopic characterisation, molecular and electronic structures, and properties of these intriguing species, and compares these aspects of their behaviour with those of isoelectronic sulfur oxides and N,O anions. A final section draws attention to the significance and applications of these simple S-N species in a broader context.

Insights into the formation of inorganic heterocycles via cyclocondensation of primary amines with group 15 and 16 halides.

Cyclocondensation is a major preparative route for the generation of inorganic heterocycles especially in the case of ring systems involving a Group 15 or 16 element linked to nitrogen. This Perspective will consider recent experimental and computational studies involving the reactions of primary amines (or their synthetic equivalents) with pnictogen and chalcogen halides. The major focus will be a discussion of the identity and role of acyclic intermediates in the reaction pathways to ring formation, as well as the nature of the heterocycles so formed. The similarities and differences between the chemistry of group 15 and 16 systems are emphasised with a view to providing signposts for further investigations.

DFT calculations in the assignment of solid-state NMR and crystal structure elucidation of a lanthanum(iii) complex with dithiocarbamate and phenanthroline.

The molecular, crystal, and electronic structures as well as spectroscopic properties of a mononuclear heteroleptic lanthanum(iii) complex with diethyldithiocarbamate and 1,10-phenanthroline ligands (3 : 1) were studied by solid-state 13C and 15N cross-polarisation (CP) magic-angle-spinning (MAS) NMR, X-ray diffraction (XRD), and first principles density functional theory (DFT) calculations. A substantially different powder XRD pattern and 13C and 15N CP-MAS NMR spectra indicated that the title compound is not isostructural to the previously reported analogous rare earth complexes with the space group P21/n. Both 13C and 15N CP-MAS NMR revealed the presence of six structurally different dithiocarbamate groups in the asymmetric unit cell, implying a non-centrosymmetric packing arrangement of molecules. This was supported by single-crystal X-ray crystallography showing that the title compound crystallised in the triclinic space group P1[combining macron]. In addition, the crystal structure also revealed that one of the dithiocarbamate ligands has a conformational disorder. NMR chemical shift calculations employing the periodic gauge including projector augmented wave (GIPAW) approach supported the assignment of the experimental 13C and 15N NMR spectra. However, the best correspondences were obtained with the structure where the atomic positions in the X-ray unit cell were optimised at the DFT level. The roles of the scalar and spin-orbit relativistic effects on NMR shielding were investigated using the zeroth-order regular approximation (ZORA) method with the outcome that already the scalar relativistic level qualitatively reproduces the experimental chemical shifts. The electronic properties of the complex were evaluated based on the results of the natural bond orbital (NBO) and topology of the electron density analyses. Overall, we apply a multidisciplinary approach acquiring comprehensive information about the solid-state structure and the metal-ligand bonding of the heteroleptic lanthanum complex.

Synthesis, characterization, and ligand behaviour of a new ditelluroether (C10H7)Te(CH2)4Te(C10H7) and the concurrently formed ionic [(C10H7)Te(CH2)4]Br.

The reaction of 1-naphthyl bromide with n-butyl lithium, elemental tellurium, and 1,4-dibromobutane in THF affords both (C10H7)Te(CH2)4Te(C10H7) (1) and [(C10H7)Te(CH2)4]Br (2) in good yields. 1 is preferentially formed at low temperatures and is a rare example of a structurally characterized ditelluroether in which the tellurium atoms are bridged by a hydrocarbon chain. In the solid state, 1 shows secondary bonding TeTe interactions, which connect the molecules into layers which are further linked to 3-dimensional frameworks by TeH hydrogen bonds. [(C10H7)Te(CH2)4]Br (2) is formed concurrently during the synthesis of 1 and is the main product, when the reaction is carried out at room temperature. The revPBE/def2-TZVPP calculations of the reaction profiles indicate that the formation of 2 is somewhat more favourable than that of 1. Furthermore, at room temperature the activation energy for the formation of 2 is lower than that of 1. At low temperatures the activation energy of the reaction leading to 1 is lower than that to 2, which is consistent with the synthetic observations. When 1 was treated with CuBr, [Cu2(µ-Br)2{µ-(C10H7)Te(CH2)4Te(C10H7)}2] (3) was formed. It crystallizes as two polymorphs (3a) and (3b) in which both the packing and the conformation of the ditelluroether ligands are different. The reaction of 1 with HgCl2 produces [(C10H7)Te(CH2)4]2[HgCl4]·CH2Cl2 (4·CH2Cl2) and that of 1 with CuCl2 affords [(C10H7)Te(CH2)4]Cl (5). 2 and 5 are isomorphous.

Theoretical and Synthetic Study on the Existence, Structures, and Bonding of the Halide-Bridged [B2X7](-) (X = F, Cl, Br, I) Anions.

While hydrogen bridging is very common in boron chemistry, halogen bridging is rather rare. The simplest halogen-bridged boron compounds are the [B2X7](-) anions (X = F, Cl, Br, I), of which only [B2F7](-) has been reported to exist experimentally. In this paper a detailed theoretical and synthetic study on the [B2X7](-) anions is presented. The structures of [B2X7](-) anions have been calculated at the MP2/def2-TZVPP level of theory, and their local minima have been shown to be of C2 symmetry in all cases. The bonding situation varies significantly between the different anions. While in [B2F7](-) the bonding is mainly governed by electrostatics, the charge is almost equally distributed over all atoms in [B2I7](-) and additional weak iodine···iodine interactions are observed. This was shown by an atoms in molecules (AIM) analysis. The thermodynamic stability of the [B2X7](-) anions was estimated in all phases (gas, solution, and solid state) based on quantum-chemical calculations and estimations of the lattice enthalpies using a volume-based approach. In the gas phase the formation of [B2X7](-) anions from [BX4](-) and BX3 is favored in accord with the high Lewis acidity of the BX3 molecules. In solution and in the solid state only [B2F7](-) is stable against dissociation. The other three anions are borderline cases, which might be detectable under favorable conditions. However, experimental attempts to identify [B2X7](-) (X = Cl, Br, I) anions in solution by (11)B NMR spectroscopy and to prepare stable [PNP][B2X7] salts failed.

The role of imidoselenium(II) chlorides in the formation of cyclic selenium imides via cyclocondensation.

The third member of the series of imidoselenium(II) chlorides ClSe[N(tBu)Se]nCl (n = 3) (9) has been isolated from the cyclocondensation reaction of tBuNH2 and SeCl2 in THF in a molar ratio of ca. 3:1 and characterized in the form of two polymorphs 9a and 9b by single crystal X-ray analysis. The unusual structural features of this nine-atom chain are explained satisfactorily in terms of a bonding model that invokes intra-molecular secondary bonding interactions and hyperconjugation. The reaction of the bifunctional reagent ClSe[N(tBu)Se]2Cl (8) with tBuNH2 in THF occurs via concurrent pathways to give 1,3,5-Se3(NtBu)3 (1) and 1,3-Se3(NtBu)2 (3a). The energetics of the reactions of tBuNH2 and SeCl2 in THF have been calculated at the PBE0/def2-TZVPP level of theory in order to assess the feasibility of ClSe[N(tBu)Se]nCl (7­9, n = 1­3) as intermediates in the formation of known cyclic selenium imides. DFT calculations were also employed to explore the energy profile of the pathway of the formation of the first member of the series ClSeN(tBu)SeCl (7) from tBuNH2 and SeCl2 in THF at 298 K. The neutral ligand ClSeN(tBu)SeCl (7) is Se,Se'-coordinated to the metal centre in the unusual adduct [PdCl2{Se,Se'-(SeCl)2N(tBu)}]·[PdCl2{Se,Se'-Se4(NtBu)3}]·MeCN (10·MeCN), which is the first metal complex of an imidoselenium(II) chloride.

Mercury- and cadmium-assisted [2 + 2] cyclodimerization of tert-butylselenium diimide.

The complexes [MCl2{N,N'-(t)BuNSe(µ-N(t)Bu)2SeN(t)Bu}] [M = Cd (1), Hg (2)] were obtained in high yields by the reaction of tert-butylselenium diimide Se(IV)(N(t)Bu)2 with CdCl2 or HgCl2 in tetrahydrofuran. Recrystallization of 1 and 2 from acetonitrile (MeCN) afforded yellow crystals of 1·MeCN and 2·MeCN, respectively. Isomorphic 1·MeCN and 2·MeCN contain an unprecedented dimeric selenium diimide ligand, which is N,N'-chelated to the metal through exocyclic imido groups. In addition to the complexes 1 and 2, the (77)Se NMR spectra of acetonitrile solutions of 1·MeCN and 2·MeCN indicated the presence of the dimeric (t)BuNSe(µ-N(t)Bu)2SeN(t)Bu, monomeric Se(IV)(N(t)Bu)2, and cyclic selenium imides. Density functional theory calculations at the PBE0/def2-TZVPP level of theory were used to assign the (77)Se resonances of the dimer. A comparison of Gibbs energies of formation of some metal dichloride complexes [MCl2{N,N'-Se(IV)(N(t)Bu)2}] and [MCl2{N,N'-(t)BuNSe(µ-N(t)Bu)2SeN(t)Bu}] (M = Zn, Cd, Hg) indicated that the formation of complexes containing a dimeric selenium diimide ligand is favored over those containing a monomeric ligand for the group 12 metals. In the case of the group 10 metal halogenides (M = Ni, Pd, Pt), the Gibbs energies of the complexes with monomeric Se(IV)(N(t)Bu)2 ligands are close to those containing dimeric (t)BuNSe(µ-N(t)Bu)2SeN(t)Bu ligands. A plausible reaction pathway with a low activation energy involves the initial formation of [MCl2{N,N'-Se(IV)(N(t)Bu)2}] (M = Zn, Cd, Hg), which then reacts with another molecule of Se(N(t)Bu)2, leading to the final [MCl2{N,N'-(t)BuNSe(µ-N(t)Bu)2SeN(t)Bu}] complex. Without the presence of group 12 metal halogenides, the [2 + 2] cyclodimerization of Se(IV)(N(t)Bu)2 is virtually thermoneutral, but the activation energy is relatively high, which accounts for the kinetic stability of (t)BuNSe(µ-N(t)Bu)2SeN(t)Bu in solution. A minor byproduct, [Cd7Cl14{N,N'-Se(II)(NH(t)Bu)2}6]·4CH2Cl2, was identified by X-ray crystallography as a heptanuclear cluster with selenium(II) diamide ligands N,N'-chelated to the cadmium centers.

Experimental and Computational (77)Se NMR Investigations of the Cyclic Eight-Membered Selenium Imides 1,3,5,7-Se4(NR)4 (R = Me, (t)Bu) and 1,5-Se6(NMe)2.

The cyclocondensation reaction of equimolar amounts of SeCl2 and (Me3Si)2NMe in THF affords 1,3,5,7-Se4(NMe)4 (5b) [δ((77)Se) = 1585 ppm] in excellent yield. An X-ray structural determination showed that 5b consists of cyclic, puckered crown-shaped molecules with a mean Se-N bond length of 1.841 Å typical of single bonds. A minor product of this reaction was isolated as unstable orange-red crystals, which were identified by X-ray analysis as the adduct 1,5-Se6(NMe)2·(1)/2Se8 (1b·(1)/2Se8), composed of cyclic 1,5-Se6(NMe)2 and disordered cyclo-Se8 molecules. A detailed reinvestigation of the cyclocondensation reaction of SeCl2 and (t)BuNH2 as a function of molar ratio and time by multinuclear ((1)H, (13)C, and (77)Se) NMR spectroscopy revealed that the final product exhibits one (77)Se resonance at 1486 ppm and equivalent N(t)Bu groups. The shielding tensors of 28 selenium-containing molecules, for which the (77)Se chemical shifts are unambiguously known, were calculated at the PBE0/def2-TZVPP level of theory to assist the spectral assignment of new cyclic selenium imides. The good agreement between the observed and calculated chemical shifts enabled the assignment of the resonance at 1486 ppm to 1,3,5,7-Se4(N(t)Bu)4 (5a). Those at 1028 and 399 ppm (intensity ratio 2:1) could be attributed to 1,5-Se6(NMe)2 (1b).

Tellurium: a maverick among the chalcogens.

The scant attention paid to tellurium in both inorganic and organic chemistry textbooks may reflect, in part, the very low natural abundance of the element. Such treatments commonly imply that the structures and reactivities of tellurium compounds can be extrapolated from the behaviour of their lighter chalcogen analogues (sulfur and selenium). In fact, recent findings and well-established observations clearly illustrate that this assumption is not valid. The emerging importance of the unique properties of tellurium compounds is apparent from the variety of their known and potential applications in both inorganic and organic chemistry, as well as materials science. With reference to selected contemporary examples, this Tutorial Review examines the fundamental concepts that are essential for an understanding of the unique features of tellurium chemistry with an emphasis on hypervalency, three-centre bonding, secondary bonding interactions, σ and π-bond energies (multiply bonded compounds), and Lewis acid behaviour.

Crystal structure of bis-{µ-2-[(di-methyl-amino)-meth-yl]ferrocene-seleno-lato}bis[chlorido-palladium(II)].

The dinuclear title compound, [PdCl{Se[(C5H5)Fe(C5H3)2CH2N(CH3)2]}]2 was obtained by the reaction of [PdCl2(NCPh)2] with 2-[(N,N'-di-methyl-amino)-meth-yl]ferro-cene-seleno-late and the crystals for the structure determination were grown from a mixture of THF and n-hexane. Both Pd(II) atoms are coordinated by the bridging Se atoms and by the amino N atoms of the bidentate 2-[(N,N'-di-methyl-amino)-meth-yl]ferrocene-seleno-late ligand, as well as by Cl atoms, and show a distorted square-planar coordination. The angle between the Pd-Se-Se planes of the two Pd atoms is 149.31 (3)°. Weak Cl⋯H hydrogen bonds link the binuclear complexes into a three-dimensional network.