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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Referring to numbered atom (e.g. C-1 vs C1)
Is there a recommended style how to designate an atom by its number according to the structure numbering (given by nomenclature, or any other one in the text context)?
The are (at least) two ...
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Platt's Notation/Nomenclature for transitions
How do you read Platt's Notation / Nomenclature? Where can I learn this?
Some examples where I've seen this mentioned:
In Platt's notation the transitions are designated as $\ce{A -> B}$ and $\ce{...
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What are the essential arrows for entering chemical equations in text?
I'm the author of a custom chemistry keyboard on iOS. I am looking at improving the selection of Unicode arrows I can provide. When the device is a phone in portrait mode, I don't have a lot of extra ...
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Is it correct to use the symbols (l) and (g) in every reaction?
I know that this question might sound stupid to most of the people, but for a chemist noob like me is not very clear. So, here's the main question:
Is it appropriate to use the symbols (l) for ...
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Meaning of $^2[\,1/2]$ terms in atomic spectroscopy
I was trying to analyze some atomic emission spectroscopy data and I encountered unfamiliar notation of the terms for me.
Commonly, the electronic states of the atoms can be described by quantum ...
user76255
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Is a change in delta-delta-G typically notated as delta-delta-delta-G?
I'm currently writing a research paper, and need to refer to a difference between $\Delta{\Delta}G$s. The naive way to notate this would be $\Delta{\Delta}{\Delta}G$, but that looks cumbersome and ...
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Is there a particular name for a Hill formula or sum formula omitting hydrogen?
Often, single-crystal X-ray diffraction analysis determines the non-H atoms first, and eventually puts hydrogen atoms "as riding" on idealized positions in respect to heavier atoms (e.g., C, O, N), ...
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Side chain formation in polymerisation of ethylene
I am having difficulty understanding (or at least need confirmation of my understanding) of this diagram regarding the formation of sidechains of polyethylene. If someone could explain it, that would ...
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Raoult's law: is the molar fraction the molar fraction in the entire system?
I have two physical chemistry textbooks, one by Atkins and one by Levine, which seem to differ in their notation used when describing Raoult's law.
Atkins talks about the molar fraction term in ...
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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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Multiplicity letter codes for large amount of states
Well, let's say we have a large amount of states computed (e.g. over 50), all with the same multiplicity.
So, our ground state can be $X^2\Sigma^+_g$ and we can continue with $B^2, C^2$ etc. as ...
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State symbol for electron
Is it correct to write a state symbol of "g" or "l" for an electron? In the textbook I am currently reading, the state symbol "g" was used for the electron when it described the electron gain by a ...
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What do γ (gamma) and λ (lambda) mean in organic chemistry?
From the Wikipedia entry on Cyhalothrin:
Pyrethroids such as cyhalothrin are often preferred as an active
ingredient in agricultural insecticides because they are more
cost-effective and longer ...
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Is there a standardized way to assign a label to the symbol of a chemical element (in a published work)?
When referring to a particular atom, both in text and when using a graphical representation, several conventions are being applied.
In the field of crystallography an arabic numeral either follows ...
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Formating chemical equations for proteins binding in multiple configurations
I am working on problems involving protein-protein binding, particularly ones in which two proteins may bind in two or more configurations, and where some of the resultant structures may also bind ...
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