Second Order Jahn‐Teller Effect in Hexahalogenotellurates(IV): Statically Distorted Anion in Ca(H₂O,HF)₇TeBr₆

Abstract

The gene fragments were ligated with the aid of polynucleotide ligase to form the complete gene (Fig. 2), which was then inserted into a plasmid opened with EcoRI and IFN-I IFN-I1 IFN-111 t p I F N Eco R I Barn H I Fig. 2. Cloning vectors pUC8 and pUC9 with the gene fragments IFN-I-IFN-Ill and expression vectors pMX2 with the tac-regulation unit. For the construction of the expression vector pMX2 the gene fragments IFN-I-IFN-111 were first subcloned in pUC8 and pUC9, respectively, as follows: 1 pg of the pUC plasmid (BRL, Neu-Isenberg) was digested with 2 to 5 units of the desired restriction endonucleases at 37°C for 2 h in a buffer according to the manufacturers instructions. The back-bone plasmid was then separated from the cleaved oligonucleotides by electrophoresis on a 0.7% low melting point agarose gel. After cutting out the desired bands, melting the gel at 60"C, phenol and ether extraction of the aqueous phase, the plasmid-DNA was isolated by precipitation with ethanol. 0.1 Fg of the opened plasmid was subsequently ligated with 0.2 pg of the respective synthetic DNA fragment with the aid of 10 units T4-DNA-ligase at 4°C for ca. 15 h and transformed by the usual CaCI2-method in E. coli. 7902. Clones with hybrid plasmids were worked-up according to a rapid lysate-method by treatment with alkali 191 and analyzed on the basis of the restriction enzyme cleavage pattern on 10% agarose gels. The gene fragments IFN-I-IFN-111 were cleaved from the pUC vectors with the respective restriction endonucleases, reisolated by electroelution, phenol extracted, and precipitated with ethanol.The correctness of the two DNA strands was verified by sequencing according to the method of Maxam and Gilbert [7]. The total gene for y-IFN was then obtained by ligation of the three gene fragments IFN-I, IFN-11, and IFN-I11 and once again incorporated into an expression plasmid "downstream" from the control region (trp-lac fusion promotor, lac-operator) IS], in the same way as described for the subfragments.

The lone electron pair and crystal packing: observations on pyramidal YEL3ε species, abinitio calculations, and the crystal structures of Me3SOI, Et3SI, (Me3S)2SnCl6, (Me3SO)2SnCl6, and (Et3S)2SnCl6

“…Abriel (75)(76)(77)(78)(79) found that in contrast to the appreciably distorted TeC16 octahedron in [H3N(CH2)3NH3]-TeC16 the SnC16 octahedron in the corresponding hexachlorostannate(1V) is undistorted. The distortion observed in the TeC162-and ~e~r 6 ' -ions is accompanied by lifting of the degeneracy of the v3(tlu) and v4(tlu) fundamentals in the ir spectra; however, the v3 and v4 absorption bands appear to be broadened even in cubic Rb2TeBr6, where Te is at a site of Oh symmetry.…”

Nonoctahedral Structures

“…The slightly larger Se atom in SeF 6 2- is the borderline case. If the central atom sizes are kept equal, but the size of the ligand atom is increased as in TeCl 6 2- , TeBr 6 2- , and TeI 6 2- , then again the structure changes toward octahedral. , The resulting prediction is also fulfilled, namely that with the increasing number of ligands, the sterical activity of the nonbonding electron pair diminishes and disappears. XeF 5 + has a square pyramidal umbrella structure, with the sterically active lone pair occupying an apical site.…”

“…In such highly symmetric molecules, this is difficult to prove experimentally. But derivatives of the kind F 5 Mo-OR and F 5 W-OR (with R ) CH 2 -CF 3 and C 6 F 5 ) show coalescence of the chemically different fluorine atoms in the 19 F NMR spectrum not much above room temperature. 46 Chemical thinking immediately brings up mixed substituted compounds (CH 3 ) x MoX 6-x and (CH 3 ) x WX 6-x (with X ) F, Cl, OR) to answer the question, at what stage of substitution the change occurs from trigonal prism to octahedron or vice versa.…”

Halide Perovskite-Derived Compounds Rb2TeX6 (X = Cl, Br, and I): Electronic Structure of the Ground and First Excited States

“…These materials include halide-perovskite-derived complexes, − the most promising of which are complexes with the general formula A 2 BX 6 (where A is organic or inorganic cations, B are so-called s 2 -ions (Ti IV , Hf IV , Zr IV , Pd IV , Pb II , Sn IV , Te IV , Sb III , and Bi III ), and X are halogens (F, Cl, Br, and I)). These compounds possess interesting luminescent, optical, dielectric, and magnetic properties and have applications in modern semiconductor devices. − Currently, these materials are used to increase the power of photovoltaic modules − or increase the luminescence quantum yield. − …”

“…On binding cations, they form structures with densely packed layers. Crystals with [TeCl 6 ] 2– and [TeBr 6 ] 2– anions have strong luminescent properties, ,,, whereas those with [TeI 6 ] 2– anions show polymorphism and phase transitions. − An interesting feature of these crystals is that the probability of transitions to the excited states depends mainly on the local environment of the s 2 -ion, i.e. the halogen atom.…”