40 research outputs found
On probabilistic analog automata
We consider probabilistic automata on a general state space and study their
computational power. The model is based on the concept of language recognition
by probabilistic automata due to Rabin and models of analog computation in a
noisy environment suggested by Maass and Orponen, and Maass and Sontag. Our
main result is a generalization of Rabin's reduction theorem that implies that
under very mild conditions, the computational power of the automaton is limited
to regular languages
Crystal structure of bis(μ2-methanolato-κO:κO)hexamethylbis(μ2-triphenylacetato-κO:κO′)bis(μ2-triphenylacetato-κ2O,O′:κO)dialuminiumdilanthanum toluene tetrasolvate
The title compound, [Al2La2(C20H15O2)4(CH3)6(CH3O)2]·4CH3C6H5 or [{La(Ph3CCOO)2(Me3AlOMe)}2]·4CH3C6H5, was formed in a reaction between lanthanum tris(tetramethylaluminate) and triphenylacetic acid (1:1) with unintended partial oxidation. The triphenylacetate ligand exhibits μ2-κ1O:κ1O′ bridging and μ2-κ2O,O′:κ1O semi-bridging coordination modes, forming a dimeric La2(μ-OCO)4 core. The semi-bridging triphenylacetate group provides additional bonding with an La3+ cation via the π-system of one of its phenyl rings. The trimethylmethoxyaluminate anion, which is coordinated to the La3+ cation by its O atom, displays a rather long La—CMe bond. Two toluene molecules are each disordered over two orientations about centres of symmetry with site occupancy factors of 0.5. The title compound represents the first example of an LnIII complex containing both alkyl alkoxide aluminate and π-bounded arene fragments
Bis(3,4-diphenyl)(2-methythienyl)cyclopentadienyl Terbium Chloride
A new terbium(III) complex with a (3,4-diphenyl)(2-methylthienyl)cyclopentadienyl ligand was synthesized. Single-crystal X-ray analysis revealed a binuclear biscyclopentadienyl complex with a [TbCl2K]2 core. Luminescence properties of the terbium complex were analyzed
Bis(3,4-diphenyl)(2-methythienyl)cyclopentadienyl Terbium Chloride
A new terbium(III) complex with a (3,4-diphenyl)(2-methylthienyl)cyclopentadienyl ligand was synthesized. Single-crystal X-ray analysis revealed a binuclear biscyclopentadienyl complex with a [TbCl2K]2 core. Luminescence properties of the terbium complex were analyzed