scholarly journals Cycloparaphenylene-Phenalenyl Radical and Its Dimeric Double Nanohoop

2021 ◽  
Author(s):  
Yong Yang ◽  
Olivier Blacque ◽  
Sota Sato ◽  
Michal Juricek
Keyword(s):  
Single Crystal ◽  
Steric Effect ◽  
Open Shell ◽  
Electronic Effects ◽  
X Ray Diffraction ◽  
Spin Distribution ◽  
X Ray ◽  
Donor Acceptor ◽  
Profile Characteristic ◽  
Diamond Ring

<p>We report the first example of a neutral spin-delocalized carbon-nanoring radical, achieved by integration of an open-shell graphene fragment phenalenyl into cycloparaphenylene (CPP). We show that spin distribution in this hydrocarbon partially extends from the phenalenyl onto the CPP segment as an interplay of steric and electronic effects. The resulting geometry is reminiscent of a diamond ring, with pseudo-perpendicular arrangement of the radial and the planar π-surface. Remarkably, this geometry gives rise to a steric effect that governs a highly selective dimerization pathway, yielding a giant double nanohoop. Its π-framework made of 158 sp2-carbon atoms was unambiguously elucidated by single crystal X-ray diffraction, which revealed a three-segment CPP–peropyrene–CPP structure. This nanocarbon shows a fluorescence profile characteristic of peropyrene, regardless of which segment gets excited. These results in conjunction with DFT suggest that adjustment of the size of the CPP segments in this double nanohoop could deliver true donor–acceptor systems.</p>

scholarly journals Cycloparaphenylene-Phenalenyl Radical and Its Dimeric Double Nanohoop

2021 ◽  
Author(s):  
Yong Yang ◽  
Olivier Blacque ◽  
Sota Sato ◽  
Michal Juricek
Keyword(s):  
Single Crystal ◽  
Steric Effect ◽  
Open Shell ◽  
Electronic Effects ◽  
X Ray Diffraction ◽  
Spin Distribution ◽  
X Ray ◽  
Donor Acceptor ◽  
Profile Characteristic ◽  
Diamond Ring

<p>We report the first example of a neutral spin-delocalized carbon-nanoring radical, achieved by integration of an open-shell graphene fragment phenalenyl into cycloparaphenylene (CPP). We show that spin distribution in this hydrocarbon partially extends from the phenalenyl onto the CPP segment as an interplay of steric and electronic effects. The resulting geometry is reminiscent of a diamond ring, with pseudo-perpendicular arrangement of the radial and the planar π-surface. Remarkably, this geometry gives rise to a steric effect that governs a highly selective dimerization pathway, yielding a giant double nanohoop. Its π-framework made of 158 sp2-carbon atoms was unambiguously elucidated by single crystal X-ray diffraction, which revealed a three-segment CPP–peropyrene–CPP structure. This nanocarbon shows a fluorescence profile characteristic of peropyrene, regardless of which segment gets excited. These results in conjunction with DFT suggest that adjustment of the size of the CPP segments in this double nanohoop could deliver true donor–acceptor systems.</p>

Preparation of Geminal Donor-Acceptor Units by Reactions of Low Valent Metal Halides with Iminium Chlorides

2006 ◽  
Vol 61 (2) ◽  
pp. 170-178 ◽  
Author(s):  
Xin Tian ◽  
Michael Hagemann ◽  
Roland Fröhlich ◽  
Tania Pape ◽  
Norbert W. Mitzel
Keyword(s):  
Mass Spectrometry ◽  
Single Crystal ◽  
Ionic Species ◽  
Metal Halides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Iminium Salt ◽  
Donor Acceptor ◽  
Low Valent ◽  
Work Up

AbstractThe organogallium compound [{Me2NCH2Ga(Cl,I)2}2] (1) and the organoindium compounds [Me2NCH2In(Cl,Br)2]2 (2) and [Me2NCH2InCl2]2 (3) have been prepared by the reactions of the low valent metal halides “GaI”, InBr and InCl with the iminium salt [Me2N=CH2]Cl. Compounds 1 and 2 are heterohalogen mixtures. These compounds were characterised by NMR spectroscopy and mass spectrometry, 1 furthermore by single crystal X-ray diffraction and 3 by elemental analysis. During the work-up procedure, minor amounts of hydrogen halide adducts of compounds 2 and 3 were isolated as single crystals, which contain a further equivalent of THF. These zwitter-ionic species Me2N(H)CH2In(Br,Cl)3·THF (2·H(Cl,Br)·THF) and Me2N(H)CH2InCl3 ·THF (3 ·HCl ·THF) were identified by single crystal X-ray diffraction. Methylation reactions of compounds 1 and 2 with MeLi gave two well-established compounds [{Me2NCH2GaMe2}2] and [{Me2NCH2InMe2}2], which were obtained previously by different preparation procedures.

A quinoxaline-fused tetrathiafulvalene derivative and its semiconducting charge-transfer salt: synthesis, crystal structures and physical properties

2014 ◽  
Vol 38 (5) ◽  
pp. 2052-2057 ◽  
Author(s):  
Yan Geng ◽  
Christoph Fiolka ◽  
Karl Krämer ◽  
Jürg Hauser ◽  
Vladimir Laukhin ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Charge Transfer ◽  
Physical Properties ◽  
Single Crystal ◽  
Crystal Structures ◽  
Single Crystal Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Donor Acceptor ◽  
Tetrathiafulvalene Derivative

A quinoxaline-fused tetrathiafulvalene (TTF) derivative 1 has been synthesized to form a compact and planar π-conjugated donor–acceptor (D–π–A) ensemble, and its single crystal structure has been determined by X-ray diffraction.

scholarly journals NewM+,M3+-arsenates – the framework structures of AgM3+(HAsO4)2(M3+= Al, Ga) andM+GaAs2O7(M+= Na, Ag)

2017 ◽  
Vol 73 (5) ◽  
pp. 785-790 ◽  
Author(s):  
Karolina Schwendtner ◽  
Uwe Kolitsch
Keyword(s):  
Hydrogen Bonds ◽  
Single Crystal ◽  
Diffraction Data ◽  
Room Temperature ◽  
Three Dimensional ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray ◽  
Donor Acceptor ◽  
Anionic Framework

The crystal structures of hydrothermally synthesized silver(I) aluminium bis[hydrogen arsenate(V)], AgAl(HAsO4)2, silver(I) gallium bis[hydrogen arsenate(V)], AgGa(HAsO4)2, silver gallium diarsenate(V), AgGaAs2O7, and sodium gallium diarsenate(V), NaGaAs2O7, were determined from single-crystal X-ray diffraction data collected at room temperature. The first two compounds are representatives of the MCV-3 structure type known for KSc(HAsO4)2, which is characterized by a three-dimensional anionic framework of corner-sharing alternatingM3+O6octahedra (M= Al, Ga) and singly protonated AsO4tetrahedra. Intersecting channels parallel to [101] and [110] host the Ag+cations, which are positionally disordered in the Ga compound, but not in the Al compound. The hydrogen bonds are relatively strong, with O...O donor–acceptor distances of 2.6262 (17) and 2.6240 (19) Å for the Al and Ga compounds, respectively. The two diarsenate compounds are representatives of the NaAlAs2O7structure type, characterized by an anionic framework topology built ofM3+O6octahedra (M= Al, Ga) sharing corners with diarsenate groups, andM+cations (M= Ag) hosted in the voids of the framework. Both structures are characterized by a staggered conformation of the As2O7groups.

scholarly journals Exploring short strong hydrogen bonds engineered in organic acid molecular crystals for temperature dependent proton migration behaviour using single crystal synchrotron X-ray diffraction (SCSXRD)

CrystEngComm ◽  
2019 ◽  
Vol 21 (35) ◽  
pp. 5249-5260 ◽  
Author(s):  
Lucy K. Saunders ◽  
Harriott Nowell ◽  
Lauren E. Hatcher ◽  
Helena J. Shepherd ◽  
Simon J. Teat ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Organic Acid ◽  
Single Crystal ◽  
Molecular Crystals ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Migration Behaviour ◽  
Donor Acceptor ◽  
Proton Migration

Short strong hydrogen bonds in multi-component organic acid molecular crystals exhibit temperature dependent proton migration for certain HB donor–acceptor distances.

Electron Microscopy of Shock Loaded Polycrystalline Beryllium

1974 ◽  
Vol 32 ◽  
pp. 506-507 ◽  
Author(s):  
J. M. Galbraith ◽  
L. E. Murr ◽  
A. L. Stevens
Keyword(s):  
Electron Microscopy ◽  
Wave Propagation ◽  
Structural Change ◽  
Single Crystal ◽  
Diffraction Pattern ◽  
Shock Loading ◽  
Slip Systems ◽  
Compression Tests ◽  
X Ray Diffraction ◽  
X Ray

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.

Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

2003 ◽  
Vol 218 (5) ◽  
Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören
Keyword(s):  
Crystal Structure ◽  
Inclusion Complex ◽  
Single Crystal ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
New Type

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group

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