Results 31 to 40 of about 623,551 (341)

Landau Levels versus Hydrogen Atom

Universe
The Landau problem and harmonic oscillator in the plane share a Hilbert space that carries the structure of Dirac’s remarkable so(2,3) representation.
Tekin Dereli, Philippe Nounahon, Todor Popov   +2 more
doaj   +1 more source

Tris(2-benzamidoethyl)ammonium tetrafluoroborate

Acta Crystallographica Section E, 2010
In the title compound, C27H31N4O3+·BF4−, the central N atom is protonated. The three arms form a pocket and one amidic O atom accepts an intermolecular hydrogen bond with the protonated amine. The tetrafluoroborate anion is outside the
Marcy L. Pilate, Henry Blount, Frank R. Fronczek, Md. Alamgir Hossain   +3 more
doaj   +1 more source

2s Hyperfine Structure in Hydrogen Atom and Helium-3 Ion [PDF]

, 2001
The usefulness of study of hyperfine splitting in the hydrogen atom is limited on a level of 10 ppm by our knowledge of the proton structure. One way to go beyond 10 ppm is to study a specific difference of the hyperfine structure intervals 8 Delta nu_2 -
D. J. Wineland, D. Zwanziger, G. Breit, H. A. Reich, H. A. Schluessler, H. Hellwig, J. W. Heberle, M. H. Prior, M. I. Eides, M. Sternheim, R. Arnowitt, R. Novick, S. F. Blundell, S. G. Karshenboim, S. G. Karshenboim, S. G. Karshenboim, S. G. Karshenboim, T. Kinoshita   +17 more
core   +3 more sources

rac-N-[Hydroxy(4-pyridyl)methyl]picolinamide: a hemiamidal

Acta Crystallographica Section E, 2010
The title compound, C12H11N3O2, a hemiamidal, was synthesized by solvent-free aldol condensation at room temperature by grinding picolinamide with isonicotinaldehyde in a 1:1 molar ratio.
Muhammad Altaf, Helen Stoeckli-Evans
doaj   +1 more source

Hydrogen/nitrogen/oxygen defect complexes in silicon from computational searches

, 2009
Point defect complexes in crystalline silicon composed of hydrogen, nitrogen, and oxygen atoms are studied within density-functional theory (DFT). Ab initio Random Structure Searching (AIRSS) is used to find low-energy defect structures.
Andrew J. Morris, Chris J. Pickard, R. J. Needs, R. Jones   +3 more
core   +1 more source

Mechanistic basis for inhibition of the extended‐spectrum β‐lactamase GES‐1 by enmetazobactam and tazobactam

FEBS Letters, EarlyView.
Antimicrobial resistance (AMR) is of huge importance, resulting in over 1 million deaths each year. Here, we describe how a new drug, enmetazobactam, designed to help fight resistant bacterial diseases, inhibits a key enzyme (GES‐1) responsible for AMR. Our data show it is a more potent inhibitor than the related tazobactam, with high‐level computation
Michael Beer, Philip Hinchliffe, Marko Hanževački, Christopher R. Bethel, Catherine L. Tooke, Marc W. Van der Kamp, Krisztina M. Papp‐Wallace, Robert A. Bonomo, Stuart Shapiro, Adrian J. Mulholland, James Spencer   +10 more
wiley   +1 more source

3-(4-Chlorophenyl)-5-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide

Acta Crystallographica Section E, 2013
In the title compound, C16H13ClFN3S, the pyrazole ring adopts an envelope conformation with the methine C atom being the flap atom. The chloro- and fluorobenzene rings are twisted out of the plane of the pyrazole ring [dihedral angles = 15.12 (11 ...
Edward R. T. Tiekink, Seik Weng Ng, Hanan A. Mohamed, Bakr F. Abdel-Wahab   +3 more
doaj   +1 more source

The hydrogen atom in electric and magnetic fields : Pauli's 1926 article

, 2002
The results obtained by Pauli, in his 1926 article on the hydrogen atom, made essential use of the dynamical so(4) symmetry of the bound states. Pauli used this symmetry to compute the perturbed energy levels of an hydrogen atom in a uniform electric ...
Becker H. G., Luc-Koenig E., Solov’ev E. A.   +2 more
core   +1 more source

Possible strong symmetric hydrogen bonding in disodium trihydrogen bis(2,2'-oxydiacetate) nitrate [PDF]

, 2005
In the title compound, 2Na+·C8H11O10-·NO3-, the NaI atom is heptacoordinate with an approximately pentagonal-bipyramidal geometry. A possible strong symmetric hydrogen bond, with the H atom located at an inversion centre and an OO distance of 2.450 (2) Å,
Fritsch, S., Powell, A.K., Price, D.J., Wood, P.T.   +3 more
core   +1 more source

Photosynthesis under far‐red light—evolutionary adaptations and bioengineering of light‐harvesting complexes

FEBS Letters, EarlyView.
Phototrophs evolved light‐harvesting systems adapted for efficient photon capture in habitats enriched in far‐red radiation. A subset of eukaryotic pigment‐binding proteins can absorb far‐red photons via low‐energy chlorophyll states known as red forms.
Antonello Amelii, Edoardo Andrea Cutolo, Daniele Montepietra, Claudia Battarra, Roberto Caferri, Stefano Capaldi, Zeno Guardini, Luca Dall'Osto, Roberto Bassi   +8 more
wiley   +1 more source