0000000001305075

AUTHOR

A. Alan Pinkerton

Inter- and intramolecular bonding in 1,3,5-triamino-2,4,6-trinitrobenzene: An experimental and theoretical quantum theory of atoms in molecules (QTAIM) analysis

Chemical bonding in the triclinic phase of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) has been analyzed based on the experimental electron density derived from X-ray diffraction data obtained at 20 K. The results have been compared with those from solid state theoretical calculations. The total electron density has been analyzed in terms of the Quantum Theory of Atoms in Molecules (QTAIM). Features of the covalent bonds demonstrate the presence of multiple bonds of various order. Strong intramolecular hydrogen bonds and weaker intermolecular bonds within the layer structure are characterized by the properties of their (3, −1) critical points. Weaker interactions, predominantly O···O, betwe…

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Revised structure of trans-resveratrol: Implications for its proposed antioxidant mechanism

The crystal structure of trans-resveratrol has been redetermined by X-ray diffraction. The newly refined structure demonstrates that the previously reported, dynamically disordered hydrogen-bonding network is rather the superposition of two crystallographically independent molecules of trans-resveratrol. This latter arrangement possesses a well-defined hydrogen-bonding network in a unit cell of double the previously reported volume. While not meant as a criticism of the proposed antioxidant mechanism itself, the present studies clearly show that the X-ray diffraction data should no longer be used for its additional support.

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Experimental and Theoretical Electron Density Determination for Two Norbornene Derivatives: Topological Analysis Provides Insights on Reactivity

The electron density distribution of two substituted norbornene derivatives (cis-5-norbornene-endo-2,3-dicarboxylic anhydride (1) and 7-oxabicylo[2.2.1]hept-5-ene-exo-2,3-dicarboxylic anhydride (2) has been determined from low-temperature (20 K) X-ray diffraction data and from DFT calculations with periodic boundary conditions. Topological analysis of the electron density is discussed with respect to exo-selective additions, the partial retro-Diels-Alder (rDA) character of the ground state, and intermolecular interaction energies.

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Revisiting the charge density analysis of 2,5-dichloro-1,4-benzoquinone at 20 K

A high-resolution X-ray diffraction measurement of 2,5-dichloro-1,4-benzoquinone (DCBQ) at 20 K was carried out. The experimental charge density was modeled using the Hansen–Coppens multipolar expansion and the topology of the electron density was analyzed in terms of the quantum theory of atoms in molecules (QTAIM). Two different multipole models, predominantly differentiated by the treatment of the chlorine atom, were obtained. The experimental results have been compared to theoretical results in the form of a multipolar refinement against theoretical structure factors and through direct topological analysis of the electron density obtained from the optimized periodic wavefunction. The si…

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CCDC 1508075: Experimental Crystal Structure Determination

Related Article: Christopher G. Gianopoulos, Bartosz Zarychta, Simone Cenedese, Vladimir V. Zhurov, A. Alan Pinkerton|2016|J.Phys.Chem.A|120|4059|doi:10.1021/acs.jpca.6b03787

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CCDC 1549795: Experimental Crystal Structure Determination

Related Article: Zhijie Chua, Christopher G. Gianopoulos, Bartosz Zarychta, Elizabeth A. Zhurova, Vladimir V. Zhurov, and A. Alan Pinkerton|2017|Cryst.Growth Des.|17|5200|doi:10.1021/acs.cgd.7b00674

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CCDC 1508074: Experimental Crystal Structure Determination

Related Article: Christopher G. Gianopoulos, Bartosz Zarychta, Simone Cenedese, Vladimir V. Zhurov, A. Alan Pinkerton|2016|J.Phys.Chem.A|120|4059|doi:10.1021/acs.jpca.6b03787

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CCDC 1440764: Experimental Crystal Structure Determination

Related Article: Bartosz Zarychta, Christopher G. Gianopoulos, A. Alan Pinkerton|2016|Bioorg.Med.Chem.Lett.|26|1416|doi:10.1016/j.bmcl.2016.01.070

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