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Full-Text Articles in Physical Sciences and Mathematics
Chiral Discrimination In Cyclodextrin Complexes Of Amino Acid Derivatives: Β-Cyclodextrin/N-Acetyl-L-Phenylalanine And N-Acetyl-D Phenylalanine Complexes, Jennifer M. Alexander, Joanna L. Clark, Tom J. Brett, John J. Stezowski
Chiral Discrimination In Cyclodextrin Complexes Of Amino Acid Derivatives: Β-Cyclodextrin/N-Acetyl-L-Phenylalanine And N-Acetyl-D Phenylalanine Complexes, Jennifer M. Alexander, Joanna L. Clark, Tom J. Brett, John J. Stezowski
John J. Stezowski Publications
In a systematic study of molecular recognition of amino acid derivatives in solid-state β-cyclodextrin (β-CD) complexes, we have determined crystal structures for complexes of β-cyclodextrin/N -acetyl-L-phenylalanine at 298 and 20 K and for N-acetyl-D-phenylalanine at 298 K. The crystal structures for the N-acetyl-L-phenylalanine complex present disordered inclusion complexes for which the distribution of guest molecules at room temperature is not resolvable; however, they can be located with considerable confidence at low temperature. In contrast, the complex with N-acetyl-D-phenylalanine is well ordered at room temperature. The latter complex presents an example of a complex in this series …
X-Ray Structure Of The Quinoprotein Ethanol Dehydrogenase From Pseudomonas Aeruginosa: Basis Of Substrate Specificity, Thomas Keitel, Annette Diehl, Tobias Knaute, John J. Stezowski, Wolfgang Hohne, Helmut Görisch
X-Ray Structure Of The Quinoprotein Ethanol Dehydrogenase From Pseudomonas Aeruginosa: Basis Of Substrate Specificity, Thomas Keitel, Annette Diehl, Tobias Knaute, John J. Stezowski, Wolfgang Hohne, Helmut Görisch
John J. Stezowski Publications
The homodimeric enzyme form of quinoprotein ethanol dehydrogenase from Pseudomonas aeruginosa ATCC 17933 crystallizes readily with the space group R3. The X-ray structure was solved at 2.6 Å resolution by molecular replacement. Aside from differences in some loops, the folding of the enzyme is very similar to the large subunit of the quinoprotein methanol dehydrogenases from Methylobacterium extorquens or Methylophilus W3A1. Eight W-shaped β-sheet motifs are arranged circularly in a propeller-like fashion forming a disk-shaped superbarrel. No electron density for a small subunit like that in methanol dehydrogenase could be found. The prosthetic group is located in the centre …
Structure And Lattice Dynamics Of Dipolarly Disordered 2,3-Dimethylanthracene Crystals, M. Dörr, H. Gerlach, J. Kalus, N. Karl, M. Monkenbusch, I. Natkaniec, U. Schmelzer, W. Schmidt, John J. Stezowski, P. Vorderwisch, M. Warth
Structure And Lattice Dynamics Of Dipolarly Disordered 2,3-Dimethylanthracene Crystals, M. Dörr, H. Gerlach, J. Kalus, N. Karl, M. Monkenbusch, I. Natkaniec, U. Schmelzer, W. Schmidt, John J. Stezowski, P. Vorderwisch, M. Warth
John J. Stezowski Publications
2,3-dimethylanthracene (2,3-DMA, C16H14) crystallizes in a pseudocentrosymmetric triclinic lattice with two molecules per unit cell showing dipolar structural disorder of the acentric molecules. Using powder samples the amplitude weighted phonon density of states was measured by inelastic incoherent neutron scattering for different degrees of deuteration. The differences in the resulting spectra can be explained by changes of the dynamics of the molecular bodies or the methyl side groups. By the method of inelastic coherent neutron scattering phonon dispersion curves were determined. The phonon lines are broad even at low temperatures; this fact is supposed to be …
Reply To "Comment On 'Kinetic-Energy Density Functional For A Special Shape-Invariant Potential Of A One-Dimensional Two-Level System'", Jiushu Shao, John J. Stezowski
Reply To "Comment On 'Kinetic-Energy Density Functional For A Special Shape-Invariant Potential Of A One-Dimensional Two-Level System'", Jiushu Shao, John J. Stezowski
John J. Stezowski Publications
For a harmonic potential, which is the special shape-invariant potential discussed in our paper [1], the relation between the ground state and the first-excited-state wave functions [Eq. (2)] should be . . .
Therefore, we have shown that one cannot find a closed form of the kinetic-energy density for the harmonic oscillator.
Kinetic-Energy Density Functional For A Special Shape-Invariant Potential Of A One-Dimensional Two-Level System , Jiushu Shao, John J. Stezowski
Kinetic-Energy Density Functional For A Special Shape-Invariant Potential Of A One-Dimensional Two-Level System , Jiushu Shao, John J. Stezowski
John J. Stezowski Publications
By introducing the concept of supersymmetry to quantum mechanics, several authors have shown that exactly soluble potentials, including all those well known, are easily constructed. Is the kinetic-energy density functional corresponding to these potentials a simple form? We show that the answer is no, even to the simplest one, the harmonic potential, if one builds the kinetic-energy density functional from the reduced density matrix.
Crystal Structure And Charge Transfer Energies Of Complexes Of The Donor Biphenylene With The Acceptors Tcnb And Pmda, John J. Stezowski, Rolf-Dietrich Stigler, Norbert Karl
Crystal Structure And Charge Transfer Energies Of Complexes Of The Donor Biphenylene With The Acceptors Tcnb And Pmda, John J. Stezowski, Rolf-Dietrich Stigler, Norbert Karl
John J. Stezowski Publications
Biphenylene:tetracyanobenzene (BPN:TCNB), C12H8:C10H2N4, crystallizes in a monoclinic lattice, space group P21/a, Z = 2, with a = 15.215(2) Å, b = 7.260(1) Å, c = 7.573(1) Å, β = 90.05(1)° at 296 K. The BPN donor and TCNB acceptor molecules form two symmetry-related mixed linear [001] stacks with the donor and acceptor molecular planes tilted to each other (within the individual stacks) at an angle of Φ = 7.6°. Biphenylene:pyromellitic-dianhydride (BPN:PMDA), C12H8:C10H2O6, crystallizes in two …
Phase Transition Effects: A Crystallographic Characterization Of The Temperature Dependency Of The Crystal Structure Of The 1:1 Charge Transfer Complex Between Anthracene And Tetracyanobenzene In The Temperature Range 297 To 119 K, John J. Stezowski
John J. Stezowski Publications
Crystal structures of the charge transfer complex between anthracene and tetracyanobenzene, A:TCNB, C14H10: C10H2N4, at three temperatures (297, 234 and 226 K) above the order–disorder phase transition at 206 K and at four temperatures (202, 170, 138, and 119 K) below it have been determined from x-ray diffraction data. The space group of the room temperature phase was assigned as Cm with a = 9.528(2), b =12.779(3), c = 7.441(2) Å and β=92.39(2) degrees at 297 K and for the low temperature phase is P21/a with a =9.457(1), …
Purification, Growth, Structure, Optical And Electrical Properties Of Single Crystals Of The Π-Molecular Complex Of Phenothiazine With Pyromellitic Dianhydride, R. Anthonj , N. Karl, Beverly E. Robertson, John J. Stezowski
Purification, Growth, Structure, Optical And Electrical Properties Of Single Crystals Of The Π-Molecular Complex Of Phenothiazine With Pyromellitic Dianhydride, R. Anthonj , N. Karl, Beverly E. Robertson, John J. Stezowski
John J. Stezowski Publications
Single crystals of the black phenothiazine : pyromellitic dianhydride (PTZ:PMDA) 1:1 donor–acceptor complex, have been grown by sublimation from the zone-refined components. The PTZ:PMDA complex crystalizes with PĪ symmetry (Z = 2), a = 7.197(1), b = 19.072(5), c = 6.886(1) Å, α = 84.79(1) °, β = 72.98(1) °, γ = 85.72(2) ° at T = 23 °C. The crystal structure model was refined with 5214 data { (sin ζ/λ)max = 0.8071 Å–1} to give R = 0.049 and Rw = 0.089. The crystal packing consists of two polar endless ...DADA... stacks related to …