Questions tagged [notation]
A system of written symbols used to represent qualities or quantities, elements or molecules, or formulas in general. Usually a notation follows a convention or a guideline, often published by IUPAC-IUPAP. This tag should be used for questions regarding the proper use of a notation or misleading or uncommon notation in the scientific literature. Do not confuse this tag with the [nomenclature] or [terminology] tags.
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What does ‘S/A’ mean in SMARTS pattern when using Chemicalize to draw the chemical structure?
I am still new to the SMARTS annotation. I am wondering what does S/A’ mean on the bond labeling drawn with Chemicalize using SMARTS [!#1]c1n[cH]nc([!#1])c1[!#1]? ...
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What does ‘(A)’ mean in SMARTS pattern when using Chemicalize to draw the chemical structure?
I am not quite sure what ‘(A)’ could mean for the carbon atom when writing the SMARTS CCN(C)C using Chemicalize to draw the chemical structure below. Can anyone ...
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Meaning of letter K in chemistry conventions [duplicate]
The letter "K" is usually used as chemistry (or statistics/ physics) conventions, take the equilibrium constant (Kc) and rate constant (k) as two prime examples.
Are there any reasons why &...
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Is there a symbol or representation for tolyl groups as there is for the phenyl group?
Is there a symbol or representation for tolyl groups as there is for the phenyl group?
Phenyl group is often represented by "Ph" when for a matter of space you can not draw the entire ...
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Why can you "cancel out" chemical species from a chemical equation that appear on both sides of a chemical equation?
Why is it acceptable in chemistry to "cancel out" chemical species from a chemical equation that appear on both sides of a chemical equation (as reactants and as products)?
On the one hand, ...
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How do I denote a specific rovibrational transition?
I am using a linelist from HITRAN, which gives me a whole lot of extra data and I want to denote the transitions accurately. But I don't know what to use for rovibrational transitions. The following ...
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How to obtain the expression for residual Gibbs energy?
The property involved is Gibbs free energy, the equations that I wrote are presented in my text book Introduction to chemical engineering thermodynamics by Smith and Van Ness, Chapter 6.
The thing is ...
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Parentheses use in non stoichiometric compounds
When should one use (or not) parentheses in writing the formula for non stoichiometric compounds.
I mean, the mineral sphalerite is often represented by the formula $\ce{(Zn,Fe)S}$ and, all though I ...
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What is the meaning of "*" in this compound notation?
I am reading a book on hydrogen energy (handbook of hydrogen energy), and came across the following compound on the Cu-Cl thermochemical cycle: $$\ce{CuO\text{*}CuCl_2(s)}$$
What exactly is the role ...
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How to make bonds thicker in ChemDraw?
I often see molecules depicted using ChemDraw with all or selected bonds visibly thicker than those used with the style defined with ACS-1996 template.
For example, see the PDF handouts for Baran's ...
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What do consecutive letters A and B in the 4th column of PDB file signify?
What do the consecutive A and B in the 4th column identify in a PDB file downloaded from rcsb.org?
The molecule name is 3CZ3 (...
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Notation for spectral density in experimental community
In an open quantum system setup where the system is coupled to infinite harmonic oscillators as bath (as in the Caldeira leggett model, for example), through the Hamiltonian,
$$H = \frac{\hat{p}^2}{2m}...
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Line Entry system like SMILES for metals?
SMILES is not designed for metallic compounds.
Is there a similar ASCII line entry notation for metallic compounds, including repeating structure in space, &c.?
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What is the point of the up arrow (↑) which shows "gas evolved" or "gas liberated", if you could just write the state symbol (g)? [closed]
What is the point of the up arrow (↑) which shows "gas evolved" or "gas liberated", if you could just write the state symbol (g)? And would you write the up arrows (↑) and down ...
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Total vs. Partial derivatives in kinetics
I've recently seen partial derivatives in the velocity definition but in most cases is with total derivatives (infinitesimal change of concentration over infinitesimal change of time).
Maybe is more ...
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