Chaotic Expansion of Elements of the Universal Enveloping Algebra of a Lie Algebra Associated with a Quantum Stochastic Calculus

The functional Ito formula, in the form df() = f( + d ) –f(),is formulated and proved in the context of a Lie algebra L associatedwith a quantum (non-commutative) stochastic calculus. Here fis an element of the universal enveloping algebra U of L, andf() + d() – f() is given a meaning using the coproductstructure of U even though the individual terms of this expressionhave no meaning. The Ito formula is equivalent to a chaoticexpansion formula for f() which is found explicitly. 1991 MathematicsSubject Classification: primary 81S25; secondary 60H05; tertiary18B25.     

Change of the oxidation state of phosphorus in sputtered Li3±xPO4±y and Li3±xPO4±yNz films

Thin Li_3±xPO_4±yN_zLi⁺- electrolyte films prepared by reactive rf-magnetron sputtering of Li₃PO₄ incorporate a certain amount of nitrogen which is made responsible for increased Li⁺-conductivity as well as at least kinetic stability with lithium metal. A possible change of the oxidation state +5 of phosphorus as a result of the sputter process has not yet been considered for explanation. We have found out that it cannot be generally assumed that reactive low power rf-magnetron sputtering of Li₃PO₄ results in fully oxidized films, even when pure O₂ is employed as sputtering gas. Our films immediately react with H₂O releasing a garlic smelling gas. The reaction area is surrounded by a white crust afterwards. CuSO₄ and AgNO₃ aqueous solutions become reduced. Impedance measurements yield an ionic conductivity of 2·10⁻⁶ S/cm at 25 °C and an activation energy of 0.62 eV.     

Synthesis and Sequential Deprotection of Triblock Copolypept(o)ides Using Orthogonal Protective Group Chemistry

The synthesis of triblock copolymers based on polysarcosine, poly‐N‐ε‐t‐butyloxycarbonyl‐l ‐lysine, and poly‐N‐ε‐t‐trifluoroacetyl‐l ‐lysine by ring‐opening polymerization of the corresponding α‐amino acid N‐carboxyanhydrides (NCAs) is described. For the synthesis of N‐ε‐t‐butyloxycarbonyl‐l ‐lysine (lysine(Boc)) NCAs, an acid‐free method using trimethylsilylchloride/triethylamine as hydrochloric acid (HCl) scavengers is presented. This approach enables the synthesis of lysine(Boc) NCA of high purity (melting point 138.3 °C) in high yields. For triblock copolypept(o)ides, the degree of polymerization (X_n) of the polysarcosine block is varied between 200 and 600; poly‐N‐ε‐t‐butyloxycarbonyl‐l ‐lysine and poly‐N‐ε‐t‐trifluoroacetyl‐l ‐lysine blocks are designed to have a X_n in the range of 10–50. The polypeptide‐polypeptoid hybrids (polypept(o)ides) can be synthesized with precise control of molecular weight, high end group integrity, and dispersities indices between 1.1 and 1.2. But more important, the use of tert‐butyloxycarbonyl‐ and trifluoroacetyl‐protecting groups allows the selective, orthogonal deprotection of both blocks, which enables further postpolymerization modification reactions in a block‐selective manner. Therefore, the presented synthetic approach provides a versatile pathway to triblock copolypept(o)ides, in which functionalities can be separated in specific blocks.

     

Electronic spectroscopy and computational studies of glutathionylco(III)balamin

We have studied glutathionylcobalamin (GS-Cbl) by optical spectroscopy and with density functional theory (DFT) and time-dependent DFT (TD-DFT) electronic structure methods of truncated geometric models. We examined the geometric structure of the models by comparison of DFT calculations with recent high-resolution experimental X-ray structure data ( Hannibal, L. et al. Inorg. Chem. 2010, 49, 9921) for GS-Cbl, and we examined the TD-DFT excitation simulations by comparison of the models with measured optical spectra. The calculations employed the B3LYP hybrid functional and the nonhybrid BP86 functional in both vacuum and water (conductor polarized continuum model (cpcm)) with the 6-311G(d,p) basis set. The optimized geometric structure calculations for six truncated models were made by varying the chemical structure, solvent model, and the two DFT functionals. All showed similar geometry. Charge decomposition analysis (CDA) and extended charge decomposition analysis (ECDA), especially with BP86 shows the similar charge transfer nature of the Co-S bond in GS-Cbl and the Co-C bond in CH(3)Cbl. Mayer and Wiberg bond orders illustrate the similar covalent nature of the two bonds. Finally, absolute optical spectral simulation calculations were compared with the experimental UV-visible extinction spectrum and the electronic circular dichroism (ECD) differential extinction spectrum. The BP86 method shows more spectral features, and the best fit was found for a GS-Cbl model with 5,6-dimethylbenzimidazole at the BP86/6-311G(d,p) level with a water cpcm solvent model. The excited state transitions were investigated with Martin's natural transition orbitals (NTOs). The BP86 calculations also showed π bonding interactions between Co and the axial S of the GS- ligand in the molecular orbitals (MOs) and NTOs.     

Room temperature response of SnO2-electrode modified solid state electrochemical CO2 sensors

A thin film solid state electrochemical gas sensor has been investigated for CO₂ detection based on the cell reaction: Na⁺+OH+CO₂=NaHCO₃. The galvanic cell arrangement is Au | Na_xCoO_2−δ (ref.) | NASICON | Au, SnO₂ where the right hand electrode is in contact with CO₂ and O₂ in a humid atmosphere. The response has been compared to results obtained with a conventional pellet type sensor. Furthermore, both devices have been exposed to CO and humidity. Strong cross-sensitivities were observed leading to large changes in the emf in both cases. The response to moisture is reversible and fast with a response time of about 1 min according to a fast surface reaction of H₂O with SnO₂. The presence of CO leads to a signal change with a high response time and a very slow reverse reaction. However, the response to CO₂ is not influenced by the presence of CO or H₂O with regard to the signal height and response time. Paper presented at the 3rd Euroconference on Solid State Ionics, Teulada, Sardinia, Italy, Sept. 15–22, 1996     

Untersuchungen über das Reaktionsverhalten von Antimonpentachlorid. III [1]. Zur Reaktion von Antimon (V)-chlorid mit Methylisocyanat

Studies on the Reactivity of Antimony Pentachloride. III. The Reaction of Antimony(V) Chloride and Methylisocyanate Methylisocyanate CH₃NCO reacts with SbCl₅ in boiling CCl₄ by an insertion-reaction to a product of the formula C₅H₆Cl₉N₂O₂Sb I, which has the chlorformamidinium-structure (Cl? C(O)? N(CH₃)? CCl? N(CH₃)? C(O)? Cl)⊕SbCl₆?. Hydrolysis of I yields the heterocycle C₅H₆N₂O₄ II. The reaction with methanol gives (CH₃? NH? CCl? NH? CH₃)⊕SbCl₆? III and (CH₃? NH? CCl? N(CH₃)? C(O)? OCH₃)⊕SbCl₆? IV. The i.r. and Raman spectra of the compounds I, III and IV are discussed.