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Looking for a symbol for the thermodynamic concept of conventional Temperature corresponding to \SI{298.15}{\kelvin} or \SI{25}{\Celsius} it is basically an uppercase T with a lowercase c overlaying it. Couldn't see it in the Comprehensive LaTeX Symbol List or get it through DeTeXify.

The simplest approximation I have for it is by using the following:

\rlap{T}c

which gives the following symbol

Conventional Temperature

Or define a newcommand to give it \newcommand{\Tcon}{\rlap{T}c}

Ideally the c should be shifted up from the baseline but it is good for now.

So the question is: Is there already a symbol for conventional temperature?

azetina
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Leeser
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    I have never seen this symbol before. If there really is none, you can still use Tikz. – Johannes_B Feb 17 '14 at 15:55
  • @Johannes_B. I recently came across it myself, I think it may be a makey-uppy symbol. It is used in the textbook 'Physical Chemistry' by P.W. Atkins, a standard text book, maybe he uses it as a shorthand way of expressing the 298.15 K! The above attempt will do me though! – Leeser Feb 17 '14 at 15:58
  • And should the "T" and "c" be in sans serif? – Gonzalo Medina Feb 17 '14 at 15:58
  • @GonzaloMedina No I think they should be serif, but that may just be the font of the textbook. The above image was taken from a beamer slide which had all fonts sans serif. – Leeser Feb 17 '14 at 16:01
  • @Leeser I checked my copy of Atkins: can't see the symbol. Edition and page(s)? – Joseph Wright Feb 17 '14 at 17:17
  • It's been a while since I had a copy of Atkins in my hands but I can't remember having ever seen said symbol. I only know $\theta$ (or $\vartheta$) for the temperature and $T$ for the absolute temperature. – cgnieder Feb 17 '14 at 19:44
  • @josephwright, Edition 4 page 43 it is introduced fro the first time and then appears in Tables, text and problems from there on. – Leeser Feb 18 '14 at 08:51
  • @GonzaloMedina, it appears in both serif and sans serif...Atkins Physical Chemistry ed4 pg 44, sans serif in Table and serif in equation. – Leeser Feb 18 '14 at 08:53

2 Answers2

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One option, using \ooalign (a description of \ooalign can be found in egreg's answer to \subseteq + \circ as a single symbol ("open subset")). A sans serif and a serif variant are provided:

\documentclass{article}

\newcommand\convtemp{%
  {\ooalign{T\cr\hfil\raise.2ex\hbox{c}\hfil\cr}}}
\newcommand\Convtemp{%
  {\ooalign{\textsf{T}\cr\hfil\raise.2ex\hbox{\textsf{c}}\hfil\cr}}}

\begin{document}

\convtemp\quad\Convtemp

\end{document}

enter image description here

Community
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Gonzalo Medina
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  • Forgot to mention can it be math-like, ie slanted not upright similar to output of $T$, otherwise perfect – Leeser Feb 17 '14 at 16:06
  • May i ask, where \ooalign is documented? I never came across it so far. – Johannes_B Feb 17 '14 at 16:07
  • lowlevel command see the following for a good description of how to use it...http://tex.stackexchange.com/questions/22371/subseteq-circ-as-a-single-symbol-open-subset/22375#22375 only saw this after Gonzalo's use of \ooalign – Leeser Feb 17 '14 at 16:10
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    Add a pair of braces around \ooalign{...} or funny things will happen. – egreg Feb 17 '14 at 16:11
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    @GonzaloMedina Since \ooalign issues \lineskiplimit=-\maxdimen, this setting should be made local. – egreg Feb 17 '14 at 16:16
  • @egreg Yes; I keep forgetting this (even though you warned about this in the answer I linked to). – Gonzalo Medina Feb 17 '14 at 16:20
  • @GonzaloMedina Conventional temperature is not a variable, but a fixed temperature akin to the triple point of water. \convtemp is 298.15 K so defining something as \SI{45}{\convtemp} doesn't make sense, but I like the way you did it and I now know how to declare a new siunitx unit. – Leeser Feb 18 '14 at 09:04
  • @Leeser Ah, sorry about that, I've removed the definition as a unit from my answer and I also added a sans serif version. – Gonzalo Medina Feb 18 '14 at 12:44
  • @GonzaloMedina Although \convtemp is a fixed temp, could you put back up how you assigned it as a variable and declared a new siunitx unit. I think that step was also highly informative and instructional. Maybe a "new variable" say "furlong"...:) – Leeser Feb 19 '14 at 09:11
3

Here, I use stackengine to inset the c atop the T. The 1st and 3rd arguments {c} say to place the inset with respect the horizontal and vertical center of the anchor. The 2nd argument is the horizontal offset from the center for the inset, the 4th argument is the vertical offset for the inset. The inset is the 5th argument, and the "anchor" is the last argument.

In the first 4 cases, I vary the size of the c. In the 2nd four cases, I make the c sans serif. I don't know what exactly you seek, but one of these 8 cases might get you on your way.

\documentclass{article}
\usepackage{stackengine}
\begin{document}
45 \stackinset{c}{}{c}{}{c}{T}\par
45 \stackinset{c}{}{c}{-.2pt}{\small c}{T}\par
45 \stackinset{c}{}{c}{-.2pt}{\footnotesize c}{T}\par
45 \stackinset{c}{}{c}{-.3pt}{\scriptsize c}{T}\par
45 \stackinset{c}{-.2pt}{c}{}{\textsf{c}}{T}\par
45 \stackinset{c}{-.2pt}{c}{-.2pt}{\small \textsf{c}}{T}\par
45 \stackinset{c}{-.2pt}{c}{-.2pt}{\footnotesize \textsf{c}}{T}\par
45 \stackinset{c}{-.2pt}{c}{-.3pt}{\scriptsize \textsf{c}}{T}\par
\end{document}

enter image description here

Steven B. Segletes
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