Update index.md

Author: mfherbst

index.md

@@ -10,7 +10,7 @@ You can also check us out on [GitHub](https://github.com/JuliaMolSim)!
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 Rachel and Michael gave a
 [keynote at Juliacon 2024](https://juliacon.org/2024/keynotes/#materials_modeling_bonding_across_atoms_code_and_people)
-[*Materials Modeling: Bonding across atoms, code, and people*]()https://michael-herbst.com/talks/2024.07.10_juliamolsim.pdf.
+[*Materials Modeling: Bonding across atoms, code, and people*](https://michael-herbst.com/talks/2024.07.10_juliamolsim.pdf).
 Their talk also covered the latest developments around JuliaMolSim.
 [[Slides]](https://michael-herbst.com/talks/2024.07.10_juliamolsim.pdf) [[Youtube recording]](https://www.youtube.com/watch?v=zDh6LmEGUDc)
 @@