共查询到20条相似文献,搜索用时 15 毫秒
1.
Packianathan Thomas Muthiah Kasthuri Balasubramani Urszula Rychlewska Agnieszka Plutecka 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):o605-o607
In the crystal structure of the title compound, C6H10N3+·C7H5O3−, the asymmetric unit contains four crystallographically independent 2‐amino‐4,6‐dimethylpyrimidinium and salicylate ions (Z = 8). In each of these, one of the pyrimidine N atoms is protonated, and the carboxylate group of the salicylate ion interacts with the pyrimidine group through a pair of N—H⋯O hydrogen bonds, forming an R22(8) motif. The pyrimidine cations also form base pairs via a pair of N—H⋯N hydrogen bonds (involving the amino group and the unprotonated ring N atom), forming another R22(8) motif. Three such R22(8) motifs, fused together, constitute a closed cyclic aggregate, and the linking of these aggregates, arranged in consecutive layers, can be analysed in terms of off‐face stacking interactions. 相似文献
2.
Zhi‐Min Jin Hai Feng Bing Tu Mei‐Chao Li Mao‐Lin Hu 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(10):o593-o595
The title complex, C8H6O4·2C6H7N, consists of two crystallographically independent 1:2 clusters of benzene‐1,3‐dicarboxylic acid and 4‐methylpyridine. Each cluster, the components of which are linked by O—H⋯N hydrogen bonds, is almost planar by alignment of C—H⋯O hydrogen bonds. Herring‐bone ribbons of clusters are formed by other C—H⋯O hydrogen bonds, and these ribbons are further packed to form a laminar structure by π–π interactions. 相似文献
3.
Veysel T. Yilmaz Canan Kazak Cumhur Kirilmis Murat Koca Frank W. Heinemann 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(7):o438-o441
The molecules of 2‐benzoyl‐1‐benzofuran, C15H10O2, (I), interact through double C—H⋯O hydrogen bonds, forming dimers that are further linked by C—H⋯O, C—H⋯π and π–π interactions, resulting in a three‐dimensional supramolecular network. The dihedral angle between the benzoyl and benzofuran fragments in (I) is 46.15 (3)°. The molecules of bis(5‐bromo‐1‐benzofuran‐2‐yl) ketone, C17H8Br2O3, (II), exhibit C2 symmetry, with the carbonyl group (C=O) lying along the twofold rotation axis, and are linked by a combination of C—H⋯O and C—H⋯π interactions and Br⋯Br contacts to form sheets. The stability of the molecular packing in 3‐mesityl‐3‐methylcyclobutyl 3‐methylnaphtho[1,2‐b]furan‐2‐yl ketone, C28H28O2, (III), arises from C—H⋯π and π–π stacking interactions. The fused naphthofuran moiety in (III) is essentially planar and makes a dihedral angle of 81.61 (3)° with the mean plane of the trimethylbenzene ring. 相似文献
4.
Barry A. Lloyd Atta M. Arif Evan L. Allred 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1377-1379
The title compound, endo,exo‐12‐oxotetracyclo[6.2.1.13,6.02,7]dodeca‐9‐en‐anti‐11‐yl p‐bromobenzoate, C19H17BrO3, consists of norbornene with an anti‐p‐bromobenzoate substituent at the methano bridge and an exo‐fused norbornanone unit bonded to the ethano bridge. The spatially proximate ketone and alkene interact through space and the ketone C atom is substantially pyramidalized. Through‐space ketone π‐interaction is probably responsible for the low solvolysis rate of the anti‐11‐chloride derivative. 相似文献
5.
Xiao‐Liu Wu Xiao‐Min Zhang Shu‐Yun Huang Wei‐Na Zhou Zhi‐Chang Wang 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(7):730-733
[μ‐N,N′‐Bis(pyridin‐3‐yl)benzene‐1,4‐dicarboxamide‐<!?show [forcelb]><!?tlsb=0.12pt>1:2κ2N:N′]bis{[N,N′‐bis(pyridin‐3‐yl)benzene‐1,4‐dicarboxamide‐κN]diiodidomercury(II)}, [Hg2I4(C18H14N4O2)3], is an S‐shaped dinuclear molecule, composed of two HgI2 units and three N,N′‐bis(pyridin‐3‐yl)benzene‐1,4‐dicarboxamide (L) ligands. The central L ligand is centrosymmetric and coordinated to two HgII cations via two pyridine N atoms, in a syn–syn conformation. The two terminal L ligands are monodentate, with one uncoordinated pyridine N atom, and each adopts a syn–anti conformation. The HgI2 units show highly distorted tetrahedral (sawhorse) geometry, as the HgII centres lie only 0.34 (2) or 0.32 (2) Å from the planes defined by the I and pyridine N atoms. Supramolecular interactions, thermal stability and solid‐state luminescence properties were also measured. 相似文献
6.
7.
Si‐Si Feng Li‐Ping Lu Shu‐Xia Wang Li Li Miao‐Li Zhu 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(3):m105-m108
The title compound, [FeCl2(C24H21N7)]Cl·C2H5OH·2H2O, comprises an [FeCl2(C24H21N7)]+ cation, a Cl− anion, an ethanol molecule and two water molecules. The cations are linked by π–π and C—H⋯π interactions into one‐dimensional tapes, and hydrogen bonding between the cations, Cl− anions, and ethanol and water molecules links these tapes into a three‐dimensional network. 相似文献
8.
Mustafa Serkan Soylu Nezihe alkan Alaaddin ukurovali Ibrahim Ylmaz Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):o725-o727
The title compound, C24H26BrN3OS, crystallizes in the triclinic space group P, with two independent molecules in the asymmetric unit. The molecules adopt an E geometry about the azomethine C=N double bond. The structure is stabilized as dimers by N—H⋯N hydrogen bonding. C—H⋯π and π–π interactions are also effective in the crystal packing. 相似文献
9.
《Macromolecular rapid communications》2017,38(22)
Organic solar cells based on semiconducting polymers and small molecules have attracted considerable attention in the last two decades. Moreover, the power conversion efficiencies for solution‐processed solar cells containing A–π–D–π–A‐type small molecules and fullerenes have reached 11%. However, the method for designing high‐performance, photovoltaic small molecules still remains unclear. In this review, recent studies on A–π–D–π–A electron‐donating small molecules for organic solar cells are introduced. Moreover, the relationships between molecular properties and device performances are summarized, from which inspiration for the future design of high performance organic solar cells may be obtained. 相似文献
10.
11.
12.
13.
Ligia R. Gomes John Nicolson Low James L. Wardell Laura N. de F. Cardoso Marcus V. N. De Souza 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(2):191-194
The molecules of 4‐allyloxy‐7‐chloroquinoline, C12H10ClNO, (I), 7‐chloro‐4‐methoxyquinoline, C10H8ClNO, (II), and 7‐chloro‐4‐ethoxyquinoline, C11H10ClNO, (III), are all planar. In all three structures, π–π interactions between the quinoline ring systems are generated by unit‐cell translations along the a axes, irrespective of space group. These structures are the first reported for 4‐alkoxyquinolines. 相似文献
14.
Zun‐Ting Zhang Yan‐Chang Wang 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):o51-o53
In the lattice of the title compound (systematic name: 5,6,7‐trihydroxy‐4′‐methoxyisoflavone monohydrate), C16H12O6·H2O, the isoflavone molecules are linked into chains through R43(17) motifs composed via O—H⋯O and C—H⋯O hydrogen bonds. Centrosymmetric R42(14) motifs assemble the chains into sheets. Hydrogen‐bonding and aromatic π–π stacking interactions lead to the formation of a three‐dimensional network structure. 相似文献
15.
Hole Mobility Modulation in Single‐Crystal Metal Phthalocyanines by Changing the Metal–π/π–π Interactions 下载免费PDF全文
Dr. Hui Jiang Dr. Peng Hu Dr. Jun Ye Dr. Rakesh Ganguly Dr. Yongxin Li Dr. Yi Long Prof. Denis Fichou Prof. Wenping Hu Prof. Christian Kloc 《Angewandte Chemie (International ed. in English)》2018,57(32):10112-10117
Weak intermolecular interactions in organic semiconducting molecular crystals play an important role in determining molecular packing and electronic properties. Single crystals of metal‐free and metal phthalocyanines were synthesized to investigate how the coordination of the central metal atom affects their molecular packing and resultant electronic properties. Single‐crystal field‐effect transistors were made and showed a hole mobility order of ZnPc>MnPc>FePc>CoPc>CuPc>H2Pc>NiPc. Density functional theory (DFT) and 1D polaron transport theory reach a good agreement in reproducing the experimentally measured trend for hole mobility. Additional detail analysis at the DFT level suggests the metal atom coordination into H2Pc planes can tune the hole mobility via adjusting the intermolecular distances along the shortest axis with closest parallel π stackings. 相似文献
16.
Sumesh Nicholas 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(3):211-215
The peptide N‐benzyloxycarbonyl‐L‐valyl‐L‐tyrosine methyl ester or NCbz‐Val‐Tyr‐OMe (where NCbz is N‐benzyloxycarbonyl and OMe indicates the methyl ester), C23H28N2O6, has an extended backbone conformation. The aromatic rings of the Tyr residue and the NCbz group are involved in various attractive intra‐ and intermolecular aromatic π–π interactions which stabilize the conformation and packing in the crystal structure, in addition to N—H...O and O—H...O hydrogen bonds. The aromatic π–π interactions include parallel‐displaced, perpendicular T‐shaped, perpendicular L‐shaped and inclined orientations. 相似文献
17.
Heqing Tang Lihua Zhu Yutaka Harima Kazuo Yamashita Joji Ohshita Atsutaka Kunai 《Journal of Polymer Science.Polymer Physics》1999,37(15):1873-1880
UV‐visible absorption and fluorescence properties of three series of σ–π‐conjugated polymers (copolymers of alternative oligothienylene and oligosilylene units) have been studied in dioxane solution. The energies of the absorption maximum, fluorescence maximum, and the 0–0 transition are found to be linearly dependent on the reciprocal of the number of thiophene rings in the repeating unit of the polymer chain, but almost independent of the silicon atom number. The σ–π‐conjugation in the polymers results in red shift in the absorption and fluorescence maxima, higher fluorescence quantum yields, and longer fluorescence lifetimes of the polymers, with respect to their corresponding analogous α‐oligothiophenes. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1873–1880, 1999 相似文献
18.
Manxi Zhou Min Wang Lei Zhu Zhenqing Yang Chao Jiang Dapeng Cao Qifang Li 《Macromolecular rapid communications》2015,36(24):2156-2161
The theoretical calculations are used to find that D–π–A–π–A style conjugated polymer PC‐TBTBT is more efficient for solar cells application than the D–π–A analog PC‐TBT because the D–π–A–π–A structure has a narrower band gap and higher molar absorption coefficient and redshift spectrum. Motivated by the theoretical prediction, 5,6‐bis(octyloxy)‐2,1,3‐benzothiadiazole and 2,7‐carbazole are adopted to synthesize the D–π–A–π–A style PC‐TBTBT (Mw = 31.1 kDa) and D–π–A analog PC‐TBT (Mw = 87.5 kDa) by Suzuki coupling reaction. Experimental results confirm that D–π–A–π–A PC‐TBTBT ‐based solar cell shows a power conversion efficiency (PCE) of 4.74% with high VOC of 0.99 V and enhanced JSC of 9.70 mA cm−2. The PCE and JSC achieve improvements of 17% and 26%, respectively, compared to the D–π–A PC‐TBT ‐based solar cell.
19.
Li‐Ping Lu Shu‐Qin Yao Miao‐Li Zhu 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):m220-m222
In the title compound, [Cu(C14H9NO3)(H2O)2], which crystallizes with Z = 18 in the space group R, pairs of complexes are linked into dimers by three O—H⋯O hydrogen bonds. Strong O—H⋯O hydrogen bonds link the dimers into one‐dimensional chains that further assemble into tubes through π–π and C—H⋯π interactions. 相似文献