# Tag Info

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The comments combined give a good answer: [OP] they explain two identical molecules: one is left handed and the other is right handed: From the comments: [Karsten Theis] Look at your hands, palms facing you (thumbs pointing outward). Then slowly rotate you right hand so that the thumb points left (like your left thumb). Are they the same? If in doubt, ...

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Let me take two parts from the question I can address of the bat Are d-orbitals essecial to describe bonding in 3+ periods? If we are talking about practical calculations, than yes, absolutely. d-Type basis function are a vital correction to p-orbitals. For $\ce{PF5}$ population analysis shows considerable projection of electron density on $d$-orbitals... ...

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A protonated carbonic acid (trihydroxymethyl cation) $\ce{H3CO3+}$ does exist, and is in fact incredibly stable in the solutions of superacids [1] up to $\pu{0 °C}.$ One way of obtaining $\ce{H3CO3+}$ is dissolving inorganic carbonates and hydrogen carbonates in magic acid at $\pu{-80 °C}$ [2]: \ce{CO3^2- or HCO3- ->[FSO3H-SbF5/SO2][\pu{-80 °C}] ...

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$\ce{H3CO3}$ does not exist. Why should it exist ? Where does this formula come from ? Of course you are allowed to write any formula you want. It is not forbidden to write $\ce{HC4O3}$ $\ce{H3CO5}$ $\ce{H3C2O3}$ or any other combination of C, H and O atoms that you may think of. Just for fun ! But Nature ignores your fantasy. Nobody has ever been able to ...

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It appears to be Δ⁹-tetrahydrocannabinol, also known as Δ⁹-THC: (Image source: 2D structure of tetrahydrocannabidiol (THC) by Harbin (Wikimedia)) The comment by The_Vinz about “pothead tattoo” was very … insightful.

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The term vertex (plural vertices) comes from the nomenclature used in graph theory, a branch of mathematics which describes how points in a given space are connected to each other. This turns out to be quite fundamental to chemical nomenclature, as the vertices of a graph can (generally) be chemically interpreted as an atom, and the lines coming out of a ...

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This doesn't appear to be a rare case and there are plenty $\ce{Cr^2+}$ square planar complexes. I found 15 square planar complexes with well-determined crystal structures $(R_\mathrm{int} < 10\%)$ by applying the following geometrical restrains: Chromium must have C.N. exactly 4 (T4). Chromium is allowed to be coordinated by virtually any element of ...

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An article by Bradley et al. [1] documents $\ce{[Cr(N(SiMe3)2)2(THF)2]}$ as a square planar complex. However, the $\ce{[Cr(N(SiMe3)2)3NO]}$ complex is pseudotetrahedral $(C_\mathrm{3v}).$ Figures below are provided by andselisk, the are from the reference above. References Bradley, D. C.; Hursthouse, M. B.; Newing, C. W.; Welch, A. J. Square Planar and ...

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The trigonal bipyramidal shape of $\ce{PCl5}$ is indeed the lowest energy conformation. I have had a very hard time figuring out what your description of the structure meant and I am still not convinced I have actually understood correctly. However I was trying to model it in my head I either arrived at a variety of different angles, or at least two of ...

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The shape of any molecule may be obtained by applying the VSEPR model (Valence Shell Electron Pair Repulsion). In this theory the angle between the bonds must be as large as possible. With your idea, the angles between P-Cl bonds are equal to 72°. It is not very much. In the bipyramidal model, the angles are 90° and 120°. This is much better than with your ...

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According to the authors of Ref. 1 this is a general property. They provide an explanation for the stability of such sheets based on formation of particular buckled geometries: The discovery of a flat two-dimensional crystal known as graphene has contradicted Landau−Peierls−Mermin−Wagner arguments that there is no stable flat form of such crystals. Here, ...

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This is a summary of the account by Peter Brzezinski, Professor of Biochemistry, Stockholm University, Member of the Nobel Committee for Chemistry from the Scientific Background document. [Brzezinski:] Jacques Dubochet developed methods for preparation of samples for cryo-EM studies of biomolecules in water. Joachim Frank developed methods for structural ...

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