Thin glass as a tool for architectural design

Glass with a thickness of less than 2.0 mm can be defined as a thin glass or with a thickness of less than 0.5 mm even as ultra-light. Thin glass requires for curved surfaces in order to gain structural stiffness in static use. The geometry is based on the known theory of developable surfaces. Such Façades may therefore be created from cold bent or curved laminated thin glass layers. In the past semester a seminar with architectural students were held and three projects of this seminar are worth to be presented to the public for demonstration of possibilities for use of thin glass. The definition of a seminar project for students was a connection of a big housing area with the nearby stop of the local tram which is separated by a railway line. Two possibilities for the pedestrian are given to pass the railroad. The first one is a passage underground below the railroad and the second one is a bridge above the railway line. This paper contents a study of architectural design made by students. Two projects which will be presented in this paper focuses on the design of the entrance building of a passage underground and the third project is a design of a pedestrian bridge above the railroad. Beside the architectural design a structural analysis was done to support the design process such as with ranges of possible bending radii for the curved thin glass elements and to guarantee the feasibility of the desig

Isolation, Characterization, and Computational Studies of the Novel [Mo-3(mu(3)-Br)(2)(mu-Br)(3)Br-6](2-) Cluster Anion

The novel trimolybdenum cluster [Mo-3(mu(3)-Br)(2)(mu-Br)(3)Br-6](2-) (1, Mo-3(9+), 9 d-electrons) has been isolated from the reaction of [Mo(CO)(6)] with 1,2-C2H4Br2 in refluxing PhCl. The compound has been characterized in solution by electrospray ionization mass spectrometry (ESI-MS), UV-vis spectroscopy, cyclic voltammetry, and in the solid state by X-ray analysis (counter-cations: (n-Bu)(4)N+ (1), Et4N+, Et(3)BzN(+)), electron paramagnetic resonance (EPR), magnetic susceptibility measurements, and infrared spectroscopy. The least disordered (n-Bu)(4)N+ salt crystallizes in the monoclinic space group C2/c, a = 20.077(2) angstrom, b = 11.8638(11) angstrom, c = 22.521(2) angstrom, alpha = 90 deg, beta = 109.348(4) deg, gamma = 90 deg, V = 5061.3(9) angstrom(3), Z = 4 and contains an isosceles triangular metal arrangement, which is capped by two bromine ligands. Each edge of the triangle is bridged by bromine ions. The structure is completed by six terminal bromine ligands. According to the magnetic measurements and the EPR spectrum the trimetallic core possesses one unpaired electron. Electrochemical data show that oxidation by one electron of 1 is reversible, thus proceeding with retention of the trimetallic core, while the reduction is irreversible. The effective magnetic moment of 1 (mu(eff), 1.55 mu(B), r.t.) is lower than the spin-only value (1.73 mu(B)) for S = 1/2 systems, most likely because of high spin-orbit coupling of Mo(III) and/or magnetic coupling throughout the lattice. The ground electronic state of 1 was studied using density functional theory techniques under the broken symmetry formalism. The ground state is predicted to exhibit strong antiferromagnetic coupling between the three molybdenum atoms of the core. Moreover, our calculated data predict two broken symmetry states that differ only by 0.4 kcal/mol (121 cm(-1)). The antiferromagnetic character is delocalized over three magnetic orbitals populated by three electrons. The assignment of the infrared spectra is also provided

Isolation, Characterization, and Computational Studies of the Novel [Mo₃(μ₃-Br)₂(μ-Br)₃Br ₆]²⁻ Cluster Anion

The novel trimolybdenum cluster [Mo3(μ 3-Br)2(μ -Br)3Br6]2- (1, {Mo3}9+, 9 d-electrons) has been isolated from the reaction of [Mo(CO)6] with 1,2-C2H4Br2 in refluxing PhCl. The compound has been characterized in solution by electrospray ionization mass spectrometry (ESI-MS), UV-vis spectroscopy, cyclic voltammetry, and in the solid state by X-ray analysis (counter-cations: (n-Bu)4N+ (1), Et4N+, Et3BzN+), electron paramagnetic resonance (EPR), magnetic susceptibility measurements, and infrared spectroscopy. The least disordered (n-Bu)4N+ salt crystallizes in the monoclinic space group C2/c, a = 20.077(2) Å, b = 11.8638(11) Å, c = 22.521(2) Å, α = 90 deg, β = 109.348(4) deg, γ = 90 deg, V = 5061.3(9) Å3, Z = 4 and contains an isosceles triangular metal arrangement, which is capped by two bromine ligands. Each edge of the triangle is bridged by bromine ions. The structure is completed by six terminal bromine ligands. According to the magnetic measurements and the EPR spectrum the trimetallic core possesses one unpaired electron. Electrochemical data show that oxidation by one electron of 1 is reversible, thus proceeding with retention of the trimetallic core, while the reduction is irreversible. The effective magnetic moment of 1 (μ eff, 1.55 μ B, r.t.) is lower than the spin-only value (1.73 μ B) for S = 1/2 systems, most likely because of high spin-orbit coupling of Mo(III) and/or magnetic coupling throughout the lattice. The ground electronic state of 1 was studied using density functional theory techniques under the broken symmetry formalism. The ground state is predicted to exhibit strong antiferromagnetic coupling between the three molybdenum atoms of the core. Moreover, our calculated data predict two broken symmetry states that differ only by 0.4 kcal/mol (121 cm-1). The antiferromagnetic character is delocalized over three magnetic orbitals populated by three electrons. The assignment of the infrared spectra is also provided