High-resolution melting analysis for detection of fusion allele of FUT2

The secretor status of ABH antigens, determined by FUT2 polymorphisms, affects susceptibility to various infectious diseases. In addition to many SNPs responsible for the nonsecretor phenotype, five nonfunctional alleles (se) resulting from copy number variations have been reported. One of the five alleles generated by an unequal crossover between FUT2 and a pseudogene (SEC1), is se^fus. This allele may be misidentified as a functional allele if only common inactivating SNPs are genotyped because it contains the 3ʹ region of the functional FUT2. Therefore, accurate detection of se^fus is desirable. For this purpose, a high-resolution melting (HRM) analysis is developed for detection of se^fus in which a 284bp fragment of SEC1 and se^fus but not FUT2, are amplified. This HRM analysis detected se^fus reliably. Thus, an initial screening or prescreening for se^fus using HRM analysis seems to be useful for association studies of FUT2.     

Stereo-dynamics study of O + HCl → OH + Cl reaction on the <Superscript>3</Superscript>A″, <Superscript>3</Superscript>A′, and <Superscript>1</Superscript>A′ states

Using three accurate potential energy surfaces of the ³A″, ³A′, and ¹A′ states constructed recently, we present a quasi-classical trajectory (QCT) calculation for O + HCl (v = 0, j = 0) → OH + Cl reaction at the collision energies (E _col) of 14.0–20.0 kcal/mol. The three angular distribution functions—P(q_r ) P(\theta_{r} ) , P(j_r ) P(\varphi_{r} ) , and P(q_r ,j_r ) P(\theta_{r} ,\varphi_{r} ) , together with the four commonly used polarization-dependent differential cross-sections, \frac2ps \fracds₀₀ dw_t , \frac2ps \fracds₂₀ dw_t , \frac2ps \fracds_{22 +} dw_t , \textand \frac2ps \fracds_{21 -} dw_t {\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{00} }}{{d\omega_{t} }}},\,{\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{20} }}{{d\omega_{t} }}},\,{\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{22 + } }}{{d\omega_{t} }}},\,{\text{and}}\,{\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{21 - } }}{{d\omega_{t} }}} are exhibited to get an insight into the alignment and the orientation of the product OH radical. There is a similar behavior of the tendency scattering direction for the two triplet electronic states (³A″ and ³A′)—backward scattering dominates, however, forward scattering prevails for the case of ¹A′ state. Also, obvious differences have been found in the stereo-dynamical information, which reveals the influences of the potential energy surface and the collision energy. The degrees of polarization and the influence of the collision energy on the stereo-dynamics characters of the title reaction are both demonstrated in the order of ³A′ > ³A″ > ¹A′.     

Genotyping single-nucleotide polymorphisms of human genes involved in organophosphate detoxification by high-resolution melting

Paraoxonase-1 (PON1) and butyrylcholinesterase (BCHE) are natural bioscavengers of organophosphate acetylcholinesterase inhibitors in the human body, which can determine individual sensitivity to organophosphate toxicity. Interindividual differences in activity of PON1 (catalytic bioscavenger) and substrate specificity are strongly associated with the substitution of two amino acids: Leu/Met (L/M) at position 55 (rs854560) and Gln/Arg (Q/R) at position 192 (rs662). In the case of BCHE (stoichiometric bioscavenger) substitution, Ala/Thr (A/T) at position 539 produces the so-called “K-variant” of the enzyme (rs1803274). Threonine allele is often co-inherited with an atypical BCHE allele (rs1799807). The atypical variant of BCHE displays a lower affinity for cholinesterase inhibitors. Genotyping rs662 and rs1803274 single-nucleotide polymorphisms (SNP) by high-resolution melting (HRM) is facilitated by the nucleotide substitution A>G (G>A), which resulted in a changed number of hydrogen bonds in the PCR product and, consequently, shifted T _m. In the case of rs854560, genotyping is complicated by the nucleotide substitution T>A, which has no significant effect on the T _m of the PCR product. An addition of a small quantity of LL homozygote DNA into the reaction mixture before PCR discriminates the three genotypes by the melt curves due to different amounts of heteroduplexes formed in the LM and MM samples. HRM analysis can be applied for genotyping human rs854560, rs662, and rs1803274 SNPs.

Synthesis of the One-dimensional Compound (Ph4P)[In(P2Se6)] in a Ph4P+-Containing Selenophosphate Flux,and Structure of [In(P2Se6)2]5– – a Discrete Molecular Fragment of the [In(P2Se6)]nn– Chain

The reaction of one equivalent of In with a molten flux of (Ph₄P)₂Se₅ and P₂Se₅ (1 : 2), at 250 °C gave the (Ph₄P)[In(P₂Se₆)] ( I ). Stoichiometric elemental synthesis at 750 °C produced the Cs₅In(P₂Se₆)₂ ( II ). The thin, yellow crystals of ( I ), and the irregular, dark orange crystals of ( II ), appear to be air- and water-stable. Compound ( I ) crystallizes in the monoclinic space group C2/c (no. 15) and at 23 °C: a = 23.127(7) Å, b = 6.564(1) Å, c = 19.083(3) Å, β = 97.42(2)°, V = 2873(1) ų, Z = 4, final R/R_w = 4.4/5.2%. Compound ( II ) crystallizes in the tetragonal space group P4₂/m (no. 84) and at 23 °C: a = b = 13.886(1) Å, c = 7.597(2) Å, V = 1464.9(3) ų, Z = 2, final R/R_w = 3.9/5.1%. Compound ( I ) contains infinite [In(P₂Se₆)]_n^n– with a structure related to that of K₂FeP₂Se₆. Compound ( II ) contains the discrete [In(P₂Se₆)₂]^5– which can be viewed as a fragment of the [In(P₂Se₆)]_n^n– chain.     

Synthesis and Crystal Structure of Tetrakis(tetramethylammonium) Bis[decabromotetraselenate(II)]‐bis[dibromodiselenate(I)], [(CH3)4N]4[(Se4Br10)2(Se2Br2)2], the Salt of a Mixed‐Valence Bromoselenate(II/I) Anion

Brown crystals of [NMe₄]₄[(Se₄Br₁₀)₂(Se₂Br₂)₂] ( 1 ) were obtained from the reaction of selenium and bromine in acetonitrile in the presence of tetramethylammonium bromide. The crystal structure of 1 was determined by X‐ray diffraction and refined to R = 0.0297 for 8401 reflections. The crystals are monoclinic, space group P2₁/c with Z = 4 and a = 12.646(3) Å, b = 16.499(3) Å, c = 16.844(3) Å, β = 101.70(3)° (123 K). In the solid‐state structure, the anion of 1 is built up of two [Se₄Br₁₀]^2– ions. Each shows a triangular arrangement of three planar SeBr₄ units sharing a common edge through two μ₃‐bridging bromine atoms, and one SeBr₂ molecule, which is linked to the Se^II atoms of two SeBr₄ units; between the Se₄Br₁₀^2– ions a dimerized Se₂Br₂ molecule (Se₄Br₄) is situated and one Se^I atom of each Se₂Br₂ molecule has two weak contacts [3.3514(14) Å and 3.3952(11) Å] to two bromine atoms of one SeBr₄ unit. Four Se^I atoms of a dimerized Se₂Br₂ molecule are in a almost regular planar tetraangular arrangement. Contacts between the Se^II atom of the SeBr₂ molecule and the Se^II atoms of two SeBr₄ units are 3.035(1) Å and 3.115(1) Å, and can be interpreted as donor‐acceptor type bonds with the Se^II atoms of SeBr₄ units as donors and the SeBr₂ molecule as acceptor. The terminal Se^II–Br and μ₃‐Br–Se^II bond lengths are in the ranges 2.3376(10) to 2.4384(8) Å and 2.8036(9) to 3.3183(13) Å, respectively. The bond lengths in the dimerized Se₂Br₂ molecule are: Se^I–Se^I = 2.2945(8) Å and 3.1398(12), Se^I–Br = 2.3659(11) and 2.3689(10) Å.     

[Cl5Ta(μ‐O)TaCl3{iPrS(CH2)2SiPr}] and [(TaCl4)2(μ‐O)(μ‐Me2Se2)]: two chalcogenoether complexes of Ta2OCl8 with very different geometries

The title compounds, [1,2‐bis(isopropylsulfanyl)ethane‐2κ²S,S′]octachlorido‐1κ⁵Cl,2κ³Cl‐μ‐oxido‐ditantalum(V), [Ta₂Cl₈O(C₈H₁₈S₂)], (I), and μ‐dimethyldiselane‐κ²Se:Se′‐μ‐oxido‐bis[tetrachloridotantalum(V)], [Ta₂Cl₈O(C₂H₆Se₂)], (II), contain six‐coordinate Ta^V centres linked by a nonlinear oxide bridge. Compound (I) contains one Ta^V centre bonded to a chelating dithioether and three terminal chloride ligands, with the second Ta^V centre bonded to five terminal chloride ligands. In (II), two tetrachloridotantalum(V) residues are bridged by the diselenide, giving a puckered five‐membered Ta/O/Ta/Se/Se ring. The Ta—O distances in the bridges are short in both compounds, indicating that significant multiple‐bond character is retained despite the deviation from linearity, and the bond lengths reveal a clear trans influence order of O > Cl > S > Se on the hard Ta^V centre. The structures are compared with the [Ta₂Cl₁₀O]²⁻ anion, which contains a linear oxide bridge.     

SYNTHESES AND STRUCTURES OF CLUSTER COMPOUNDS CONTAINING WSe4Cun (n = 3,4) CORES WITH DIALKYLDITHIOCARBAMATE LIGANDS

Abstract

The reactions of [Et₄N]₂[WSe₄] with three equivalents of CuCl in the presence of NaS₂CNR₂ (R = Me, Et) yielded two W-Cu-Se compounds, [Et₄N]₂[WCu₃Se₄(Et₂NCS₂)₃] (1) and [Et₄N]₂-[WCu₄Se₄(Me₂NCS₂)₄] (2). [Et₄N]₂[MoCu₃Se₄(Et₂NCS₂)₃] (1) crystallizes in the orthorhombic space group P2₁2₁2₁ with cell dimensions a = 12.976(3), b = 13.336(3) and c = 29.738(6)Å, V = 5153.8(13)ų, Z = 4. Full anisotropic refinement of the structure led to convergence at R = 0.061 (R_w = 0.070) for 453 variables and 5913 reflections with F>4.0σ(F). The [WCu₃-Se₄(Et₂NCS₂)₃]^2- anion in 1 comprises three Et₂NCS₂Cu fragments linked by a slightly distorted tetrahedral WSe₄ moiety. Compound 2 crystallizes in the orthorhombic space group Pbca with cell constants a = 14.698(3), b = 18.473(4), c = 37.182(5)Å, V = 10095.6(33) ų and Z = 8. Anisotropic refinement with 5839 reflections (F > 6.0σ(F)) and 460 parameters for all non-hydrogen atoms yielded the values R = 0.061 and R_w = 0.073. The [WCu₄Se₄(Me₂NCS₂)₄]^2- anion structure of 2 possesses pseudo D_2d symmetry for the WSe₄Cu₄ core and a nearly planar WCu₄ array and consists of four Me₂NCS₂Cu fragments coordinated across four edges of the tetrahedral [WSe₄]^2- group. IR and electronic spectroscopic data for the two compounds are reported.     

Detection of mosaicism for the polymorphic variants in the 5′‐UTR of hOGG1 by cloning and sequence analysis and pyrosequencing

Mosaicism refers to the presence of genetically distinct cell lines within an organism or a tissue. Somatic mosaicism exists in distinct populations of somatic cells and commonly arises as a result of somatic mutations, mainly in early embryonic development. SNPs are important markers that distinguish between different individuals in heterogeneous biological samples and contribute greatly to disease risk association studies. In this work, we investigated the relationship between the functional variants in the 5′‐UTR of the hOGG1 gene and the risk of type 2 diabetes. Upon detection of the polymorphisms c.‐53G>C, c.‐23A>G, and c.‐18G>T in the hOGG1 gene, we found that mosaicism was present in 3/28 (10.71%), 7/51 (13.73%), and 1/44 (2.27%) patients respectively, who were carriers of these single nucleotide variations, by cloning and sequence analysis and pyrosequencing. Statistical analysis showed that the frequency of the variation c.‐23A>G in the hOGG1 5′‐UTR in type 2 diabetic patients was significantly higher than that in healthy controls. However, sequencing of the mutant alleles in mosaic individuals showed weak peaks that may affect detection of the SNPs and impair association‐based investigations.     

The channel structure of the mercury(II) selenite(IV) oxide hydrate HgSeO3·HgO·H2O

The main building units of the title compound, dimercury(II) selenite(IV) oxide hydrate, are strongly distorted [Hg1O₆] and [Hg2O₇] polyhedra, and a pyramidal Se^IVO₃ group. Slightly corrugated hexagonal rings made up of six [Hg1O₆] octahedra spread parallel to the ab plane and are connected via [Hg2O₇] polyhedra parallel and perpendicular to this direction, which results in a three‐dimensional arrangement with channels propagating parallel to the c axis. The Se^IVO₃ groups are situated below and above the rings and bridge both types of Hg atoms. The non‐bonding orbitals are stereochemically active and protrude into the channels of the three‐dimensional network. Additional water mol­ecules are located at the centres of the channels and show weak interactions with the Se^IV lone pairs and the O atoms of the Se^IVO₃ groups.     

镉汞四元硒化物K8Cd2.79Hg9.21Se16和Rb4Hg3.04Cd2.96Se8的溶剂热合成及表征

利用溶剂热法合成了2种含镉汞的二维(2D)四元硒化物K8Cd2.79Hg9.21Se16(1)和Rb4Hg3.04Cd2.96Se8 (2)。单晶X射线衍射分析表明,化合物1为正交晶系,空间群为Pbcn,a=1.082 71(17) nm,b=0.678 73(10) nm,c=1.415 0(2) nm,Z=1;化合物2为正交晶系,空间群为Ibam,a=0.640 72(10) nm,b=1.160 25(16) nm,c=1.452 0(2) nm,Z=2。化合物1中含有八元环Cd2Hg2Se4和六元环CdHg2Se3阴离子层(Cd2.79Hg9.21Se16)n8n-;化合物2中含有八元环Cd2(Cd/Hg)2Se4及四元环CdHgSe2和(Cd/Hg)2Se2阴离子层(Hg3.04Cd2.96Se8)n4n-。对这2种化合物进行了扫描电镜和能谱分析、粉末X射线衍射、差示扫描量热分析、固体-可见漫反射光谱和荧光性质等表征。     

Synthesis and Structures of [Mo12E16(PEt3)10] (E = S,Se)

Dodecanuclcar cluster complexes [Mo₁₂S₁₆(PEt₃)₁₀] 1 and [Mo₁₂Se₁₆(PEt₃)₁₀] 2 have been prepared by the reactions of [Mo₆S₈(PEt₃)₆] with sulfur or [Mo₆Se₈(PEt₃)₆] with Cp₂TiSe₅, respectively, in toluene at refluxing temperature. The structures have been determined at 173 K by X-ray crystallography. The compound 1 ·3CHCl₃ crystallizes in the triclinic space group $ {\rm P}\bar 1 $, with a = 14.859(5) Å, b = 15.868(4) Å, c = 14.200(7) Å, α = 100.58(3)°, β = 117.58(3)°, γ = 79.53(2)°, V = 2899(1) ų, and Z = 1. Full-matrix least-squares refinement using 9016 observed reflections (I_o > 2σ(I_o)) gave R = 0.056, and R_w = 0.045. The data for 2 ·2CHCl₃ are: triclinic, $ {\rm P}\bar 1 $, a = 15.737(4) Å, b = 18.763(9) Å, c = 13.062(4) Å, α = 102.45(3)°, β = 128.54(2)°, γ = 69.49(3)°, V = 2825 ų, Z = 1, R = 0.096, and R_w = 0.120 for 5922 reflections (I_o > 2σ(I_o)). The cluster complexes 1 and 2 have two octahedral molybdenum cluster units linked by the rhomboidal intercluster Mo₂(μ₄-E)₂ bonding. The intercluster Mo—Mo distances in 1 are 3.419 Å and 2 3.551 Å. The cyclic voltammetry of 1 and 2 shows two oxidation and two reduction steps separated as large as 380–490 mV. The UV-Vis spectra of the dodecanuclear cluster complexes 1 and 2 have an extra weak band at around 744 nm which is absent in the starting octahedral cluster complexes.     

Synthese,Kristallstruktur und spektroskopische Charakterisierung von Tetraphosphorhexaoxiddiselenid P4O6Se2

Synthesis, Crystal Structure, and Spectroscopic Characterization of Tetraphosphorus Hexaoxide Diselenide P₄O₆Se₂ P₄O₆Se₂ has been prepared by photochemical selenation of P₄O₆ with red selenium in CS₂ in presence of catalytical amounts of iodine. Isolation and single crystal growth were performed by fractional crystallization and subsequent sublimation. The compound crystallizes in the monoclinic space group P2₁/c (Nr. 14) with a = 11.473(2); b = 6.536(1); c = 11.796(2) Å; β = 90.06(1)°; Z = 4; R₁ = 0.030; wR² = 0.073. Within the limits of experimental error, the P₄O₆Se₂ molecules exhibit C_2v symmetry in the crystal. Bond lengths and angles within the molecule as well as the arrangement of the molecules within the crystal are discussed; IR-, Raman-, and ³¹P solution NMR data are reported.     

Dimensional Reduction of a Selenido Stannate Salt in Ionic Liquids to form 2D-K2Sn2Se5, a Direct Heavy Analogue of an Oxo Silicate

The structural motifs of SiO₂ or silicates, on one hand, and their heavier homologues of group 14 (T) and group 16 (E) elements, on the other hand, commonly differ, as the strict adherence to corner-sharing is not necessary in the latter owing to larger interatomic distances. On the contrary: larger coordination numbers as well as edge-sharing of the coordination polyhedra are preferred in [T_xE_y] subunits with T = Si, Ge, Sn and E = S, Se, Te. Hence, we were surprised to find a new modification of the selenido stannate K₂Sn₂Se₅, which is comprised of exclusively corner-sharing [SnSe₄] tetrahedra in a layer-type anionic substructure 2D-{[Sn₂Se₅]^2–}. While the structure of the title compound 2D-K₂Sn₂Se₅ ( 1 ) differs significantly from the known parent compound, 3D-K₂Se₂Se₅, it shows similarities with layered silicates of the apophyllite family. To the best of our knowledge, 1 represents the first known selenido stannate with an oxo silicate-like 2D structure. It formed besides known selenido stannes upon heating 3D-K₂Sn₂Se₅ in in imidazolium-based ionic liquids (C₂C₂Im)[BF₄] or (C₂C₂Im)[BF₄] in the presence of DMMP and Cd²⁺ or Zn²⁺.     

Geometric and topological analysis of zeolite crystal structures by the tiling method: The model of structure of Na,K-paulingite (PAU) Na82K72[Al154Si518O1344] · wH2O

Cluster analysis of the crystal structures of paulingite zeolites (Na,Ca_0.5,K,K,Ba_0.5)₁₀[Al₁₀Si₃₂O₈₄] · 30H₂O (PAU, space group Im [`3]\bar 3 m) has been performed by the tiling method with the TOPOS program package. The tetrahedral T framework of PAU with 672 tetrahedra in the translated unit cell with a = 35.1 ? and V = 43 217 ?³ has been completely decomposed into tiles, complementarily connected polycyclic (polyhedral) T clusters. The zeolite structure is represented by an ensemble consisting of nine geometrically different nanoclusters containing 16 to 48 T tetrahedra (the linear dimensions of the nanoclusters are 12 to 18 ?, respectively). The nanoclusters correspond to seven topologically different types of tiles: 48T-grc (2a), 32T-pau (12e), 30T-plg (16f), 24T-phi (24h), 20T-gsm (12d), 16T-opr (6b, 12e), and 16T-oto (24h, 48k). In the tiles, the positions occupied by extraframework cations A = Na⁺/Ca²⁺ and B = K⁺/Ba²⁺ have been determined. The characteristic arrangement of the Na⁺/Ca²⁺ cations only at the centers of the 8T rings has been revealed, and for them a new equivalent position in the 16T-opr (6b) tile has been determined. A common crystal-chemical formula of paulingite family zeolites has been obtained: (A,B_0.5)₁₅₄[T₆₇₂O₁₃₄₄]·wH₂O; for the two outermost members, this formula takes the form A₁₅₄[T₆₇₂O₁₃₄₄]·wH₂O and B₇₇[T₆₇₂O₁₃₄₄]·wH₂O. The composition of the alkaline Na,K-paulingite A₁₅₄T₆₇₂O₁₃₄₄·wH₂O = Na₈₂K₇₂[Al₁₅₄Si₅₁₈O₁₃₄₄] ·wH₂O corresponds to the model of a structure with a maximal (100%) and ordered filling of the A cation positions: in the 16T-oto (24h, 48k) tiles for K⁺ and in the 20T-gsm (12d), 30T-plg (16f), and 16T-opr (6b, 12e) tiles for Na⁺. Such a distribution and the overall number of Na and K atoms are in good agreement with the data for synthetic paulingite analogues the (Na₈₇K₇₂TEA₁₅)[Al₁₆₄Si₅₀₈O₁₃₄₄]·wH₂O aluminosilicate and (Na_84.5K_70.5TEA_24.7)[Ga_179.7Si_492.3O₁₃₄₄]·wH₂O gallosilicate.     

Synthesis and Crystal Structure of Bis(tetraethylammonium) Octabromo‐triselenate(II)‐{dibromodiselenate(I)}, [NEt4]2[Se3Br8(Se2Br2)], the Salt of a Mixed‐valence Bromoselenate(II,I) Anion

The brown crystals of [NEt₄]₂[Se₃Br₈(Se₂Br₂)] ( 1 ) were obtained when selenium and bromine reacted in the solution of acetonitrile in the presence of tetraethylammonium bromide. The crystal structure of 1 has been determined by the X‐ray methods and refined to R = 0.0308 for 10433 reflections. The crystals are monoclinic, space group P2₁ with Z = 2 and a = 12.0393(3) Å, b = 11.8746(3) Å, c = 13.1946(3) Å, β = 96.561(1)° (123 K). In the solid state structure the anion of 1 is built up of Se₃Br₈ unit which consists of a triangular arrangement of three planar SeBr₄ units sharing a common edge through two μ₃‐bridging Br atoms, and one Se₂Br₂ molecule which is linked to one of μ₃‐bridging Br atoms. The three Se^II atoms form a triangle which is almost perpendicular to the planes given by three SeBr₄ moieties. The contact between the μ₃Br and the Se^I atom of the Se₂Br₂ molecule is 3.1711(8) Å and can be interpreted as a bond of the donor‐acceptor type with the μ₃Br as donor and the Se₂Br₂ molecule as acceptor. The terminal Se^II‐Br and μ₃Br‐Se^II bond lengths are in the ranges 2.3537(7)–2.4737(7) Å and 2.7628(7)–3.1701(7) Å, respectively. The bond lengths in coordinated Se₂Br₂ molecule are: Se^I‐Se^I = 2.2636(9) Å, Se^I‐Br = 2.3387(11) and 2.3936(8) Å.     

Synthesis and Crystal Structure of Bis(tetraphenylphosphonium) Hexabromo‐diselenate(II)‐bis{dibromodiselenate(I)}, [PPh4]2[Se2Br6(Se2Br2)2], the Salt of a Mixed‐valence Bromoselenate(II,I) Anion

The Red crystals of [PPh₄]₂[Se₂Br₆(Se₂Br₂)₂] ( 1 ) were obtained when selenium and bromine reacted in the solution of acetonitrile in the presence of tetraphenylphosphonium bromide. The crystal structure of 1 has been determined by X‐ray diffraction and refined to R = 0.0201 for 4024 reflections. The crystals are triclinic, space group with Z = 2 and a = 11.2757(4) Å, b = 12.3347(5) Å, c = 12.4948(5) Å, α = 113.152(4)°, β = 114.745(4)°, γ = 91.208(3)° (120(2) K). In the solid state the anion of 1 is built up of the Se₂Br₆ core and two Se₂Br₂ molecules each of which is linked to one of the trans‐positioned terminal Br_t atoms of the Se₂Br₆ core. The central Se₂Br₆ part consists of a nearly planar arrangement of two planar SeBr₄ units sharing a common edge through two μ₂‐bridging Br atoms. The contact between the Br_t and the Se^I atom of the Se₂Br₂ molecule is 3.0872(5) Å and can be interpreted as a bond of the donor‐acceptor type with the Br_t as donor and the Se₂Br₂ molecule as acceptor. The terminal Se^II–Br and μ₂Br–Se^II bond lengths are 2.3654(4), 2.6699(5) Å and 2.5482(5), 3.0265(5) Å, respectively. The bond lengths in the coordinated Se₂Br₂ molecule are: Se^I–Se^I = 2.2686(5) Å, Se^I–Br = 2.3779(5) and 2.3810(5) Å.     

(Se4)2[Mo2O2Cl8][MCl6](M = Zr,Hf) — Tetraselenium(2+)Halometalates with two Different Anions

The reaction of Se₄[Mo₂O₂Cl₈] with Se₄[MCl₆] (M = Zr, Hf) or of Se, SeCl₄, MoOCl₄, and MCl₄ (M = Zr, Hf) at 120 °C in sealed evacuated glass ampoules gives (Se₄)₂[Mo₂O₂Cl₈][MCl₆] (M = Zr, Hf) in the form of dark‐green, air sensitive crystals in quantitative yield. The crystal structure analyses of both isotypic compounds (monoclinic, P2₁/c, Z = 2, a = 1336(2), b = 716(1), c = 1518(4) pm, β = 106.0(2)° for M = Zr; a = 1334.1(8), b = 715.03(9), c = 1518.2(3) pm, β = 106.00(2)° for M = Hf) show the presence of square‐planar Se₄²⁺, of dinuclear [Mo₂O₂Cl₈]^2—, and of almost regular octahedral [MCl₆]^2— ions. X‐ray crystallographic investigations on (Se₄)₂[Mo₂O₂Cl₈][ZrCl₆] give no hint for solid state phase transitions between —160 and 200 °C. This is in contrast to the related compounds Se₄[Mo₂O₂Cl₈] and Se₄[ZrCl₆] which both undergo phase transitions accompanied by reorientation of the cations and anions. (Se₄)₂[Mo₂O₂Cl₈][ZrCl₆] is paramagnetic and obeys the Curie‐Weiss law with a Weiss constant of —4(7) K indicating only weak interaction between the paramagnetic centres. The magnetic moment of 1.7(1) μ_B is consistent with the presence of Mo^V (d¹ configuration) and supports the ionic formula.     

(Terpyridine)manganese(II) Coordination Polymers with Thio‐ and Selenidoarsenate(III) Ligands: Coligand Influence on the Chalcogenidoarsenate(III) Species and Coordination Mode

Hydrothermal reaction of [MnCl₂(terpy)] with elemental As and Se at 150 °C in 1:2:4 and 1:4:8 molar ratios in the presence of Cs₂CO₃ affords the complexes [{Mn(terpy)}₂ (As₂Se₅)]₂ ( 1 ) and [{Mn(terpy)}₂ (As₄Se₈)] ( 2 ), respectively. 1 contains dipyramidal [As₂Se₅]^4? ligands that bridge three Mn^II atoms in a tetradentate μ₃‐1κ²Se¹,Se²:2κSe⁴:3κSe⁵ manner. The tetranuclear complex is centrosymmetric and exhibits a central 8‐membered (MnSeAsSe)₂ ring. Cyclic [As₄Se₈]^4? ligands are present in the centrosymmetric dinuclear complex 2 and chelate the Mn(II) atoms through adjacent terminal Se atoms. Both 1 and 2 are linked into infinite chains through weak Mn···Se interactions. [{Mn(terpy)}₂(As₄S₈)] ( 3 ) and ( 4 ) can be obtained by hydrothermal reaction of [MnCl₂(terpy)] with As₂S₃ at respectively 150 °C and 190 °C. Whereas 3 exhibits an identical connectivity pattern to that of 2 , the coordination polymer 4 contains vierer chains that coordinate {(terpy)Mn}²⁺ fragments in a bidentate manner through terminal S atoms. The complex ( 5 ) contains double chains and results from the analogous hydrothermal reaction of [MnCl₂(tren)] with As₂S₃ at 150 °C.     

Synthesis and Crystal Structure of Bis(methyltriethylammonium) Hexabromotellurate(IV)‐tris{dibromodiselenate(I)}, [NMeEt3]2n[TeBr6(Se2Br2)3]n,Containing a Chain‐Polymeric Mixed‐valence Bromotellurate(IV)‐Selenate(I) Anion

Red crystals of [NMeEt₃]_2n[TeBr₆(Se₂Br₂)₃]n ( 1 ) were isolated when selenium and bromine (1:1) were allowed to react in acetonitrile solution in the presence of tellurium(IV) bromide and methyltriethylammonium bromide (1:2). The salt 1 crystallizes in the monoclinic space group C2/c with the cell dimensions a = 27.676(6) Å, b = 9.665(2) Å, c = 18.796(4) Å and ß = 124.96(3)° (120 K). The [TeBr₆(Se₂Br₂)₃]^2— anions contain nearly regular octahedral [TeBr₆]^2— ions which are incorporated into a polymeric chain by bonding contacts between 3 facial bromo ligands and 3 Se₂Br₂ molecules, one of which is situated on the twofold symmetry axis. The distances between the μBr ligands and the Se^I atoms of the Se₂Br₂ molecules are observed in the range 3.308(2) — 3.408(2) Å and can tentatively be interpreted as donor‐acceptor bonds with μBr as donors and Se₂Br₂ as acceptors. The Te^IV—Br distances are in the range 2.669(1) — 2.687(1) Å. The bond lengths in the connecting Se₂Br₂ molecules are: Se^I—Se^I = 2.267(2) and 2.281(2) Å, Se^I—Br = 2.340(1), 2.353(1) and 2.337(1) Å.     

Bis(diethoxyselenophosphinoyl) triselenide and bis(diisopropoxyselenophosphinoyl) diselenide

The title compounds, bis(diethoxyselenophosphinoyl) triselenide, [P(OEt)₂Se]Se₃[P(OEt)₂Se], and bis­(diisopropoxy­selenophosphinoyl) diselenide, [P(OⁱPr)₂Se]Se₂[P(OⁱPr)₂Se], comprise an Se₃ chain or an Se₂ chain bridging two (RO)₂PSe groups.