Topic
Pentagonal pyramid
About: Pentagonal pyramid is a research topic. Over the lifetime, 99 publications have been published within this topic receiving 1165 citations. The topic is also known as: J2.
Papers published on a yearly basis
Papers
TL;DR: The crystal structure of the title complex determined from three-dimensional diffractometer data has been determined from 3D diffractometry data as mentioned in this paper, and the exact absolute configuration of the molecule is known.
Abstract: The crystal structure of the title complex determined from three-dimensional diffractometer data. Z= 4 in an orthorhambic unit cell having a= 12·271, b= 9·550, c= 15·719 A, and space group P212121. Full-matrix least-squares refinement based on 887 observations has led to R 0·048 for the correct absolute configuration of the molecule.The sodium ion is surrounded by a pentagonal pyramid of oxygen atoms. The base is formed by those of the cyclic ether with Na–O 2·35(1)–2·43(1)A and the sodium ion is 0·75 A from this plane towards the apical water molecule, Na–O 2·29(1)A. The iodide ion does not interact with the sodium ion but may form hydrogen bonds to water molecules [O⋯I 3·47(1) and 3·51(1)A], linking the complexes in chains along the b-axis of the crystal.
63 citations
TL;DR: The compound C(s)-C(60)(CF(3))(6) is the first [60]fullerene derivative with adjacent R(f) groups that are sufficiently sterically hindered to cause the (DFT-predicted) lengthening of the cage as well as to give rise to a rare, non-fast-exchange-limit NMR spectrum at 20 degrees C.
Abstract: Reaction of C60 with CF3I at 550 °C, which is known to produce a single isomer of C60(CF3)2,4,6 and multiple isomers of C60(CF3)8,10, has now been found to produce an isomer of C60(CF3)6 with the Cs-C60X6 skew-pentagonal-pyramid (SPP) addition pattern and an epoxide with the Cs-C60X4O variation of the SPP addition pattern, Cs-C60(CF3)4O. The structurally similar epoxide Cs-C60(C2F5)4O is one of the products of the reaction of C60 with C2F5I at 430 °C. The three compounds have been characterized by mass spectrometry, DFT quantum chemical calculations, Raman, visible, and 19F NMR spectroscopy, and, in the case of the two epoxides, single-crystal X-ray diffraction. The compound Cs-C60(CF3)6 is the first [60]fullerene derivative with adjacent Rf groups that are sufficiently sterically hindered to cause the (DFT-predicted) lengthening of the cage (CF3)C−C(CF3) bond to 1.60 A as well as to give rise to a rare, non-fast-exchange-limit 19F NMR spectrum at 20 °C. The compounds Cs-C60(CF3)4O and Cs-C60(C2F5)4O are ...
51 citations
TL;DR: In this paper, the crystal structures of dithiocarbamates of AsIII, SbIII and BiIII were determined by single crystal X-ray analysis, and the results showed that the reduction process occurs around −1.0 V for As and Sb complexes and around −0.5 V for Bi complexes which are completely irreversible.
49 citations
TL;DR: A large heteropolyanion (BiW9O33)3Bi6(OH)3(H2O)3V4O10]12− has been synthesized by reaction of sodium metavanadate with Na9[BiW 9O33]·16H 2O in acetate buffer solutions (at pH 4.8) as mentioned in this paper.
49 citations
TL;DR: In this paper, the structure of MgB 4, which is based on chains of boron pentagonal pyramids in which the averaged BB bond is 1.787 A, was established from single crystal data collected on an automatic diffractometer.
40 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 3 |
| 2019 | 1 |
| 2018 | 4 |
| 2017 | 4 |
| 2016 | 3 |