# Reagent notation: meaning of dash(-) and line(|) or slash(\) in reagents

I've seen a lot of reagents which have a slash between two compounds, such as Lindlar's catalyst which is $$\ce{H2}$$ along with $$\ce{Pd|BaSO4}$$. I know that the sulphur is a poison here but in general, what does the \ or | mean? And is it supposed to be a \ or a |? Are both equivalent? Does it mean "and" or "or" or something else?

$$\ce{Cr2O3-Al2O3/Mn2O3}$$, Also what does the dash mean here? In?

EDIT: This in the context of the reagents mentioned above arrows in organic chemistry. If I'm not wrong, $$\ce{Cr2O3-Al2O3/Mn2O3}$$ is used to convert hexane to benzene by cyclization followed by aromatization.

• Generally means a reagent on a surface e.g. Pd/C or absorbed into a material e.g FeCl3/Silica Gel. The / and | are interchangeable Feb 26 '21 at 16:03
• Have a look at What is the role of the slash (“/”) in chemical reactions?, Multiple “/” in catalysts and at the related question What is the @ symbol used for in material science? Feb 26 '21 at 17:15
• Since you are asking about backslash and a pipeline, could you please provide resources where you found them or at least some more context, such as whether the formula is used in electrochemistry, catalysis or material science? All four symbols (-, /, \, |) have specific meaning based on the area they are used and are not generally interchangeable. Feb 26 '21 at 17:17
• You find the pipeline e.g. in electrochemistry to indicate the phase boundary of electrodes (an entry) like calomel, $\ce{Cl^-} | \ce{Hg2Cl2}\ | \ce{Hg} | \ce{Pt}$. Next time, add more specific context to your question, please. Feb 26 '21 at 20:55

The '|' in $$\ce{Pd|BaSO4}$$ implies that the reaction is taking place in the presence of $$\ce{Pd}$$ as a metal catalyst. This metal provides surface area for reaction to occur.
Also '/' in $$\ce{Cr2O3-Al2O3/Mn2O3}$$ means that $$\ce{Cr2O3}$$ can be used in combination with either $$\ce{Al2O3}$$ or $$\ce{Mn2O3}$$.