# How to fix the error '\[ atomtypes \]' Invalid order for directive atomtypes

**URL:** <https://gromacs.bioexcel.eu/t/how-to-fix-the-error-atomtypes-invalid-order-for-directive-atomtypes/9353>\
**Category:** User discussions\
**Created:** [June 10, 2024, 10:42pm UTC](https://gromacs.bioexcel.eu/t/how-to-fix-the-error-atomtypes-invalid-order-for-directive-atomtypes/9353 "2024-06-10T22:42:10Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Jungmin](https://avatars.discourse-cdn.com/v4/letter/j/d78d45/32.png) [@Jungmin](https://gromacs.bioexcel.eu/u/Jungmin)\
**Post date:** [June 10, 2024, 10:42pm UTC](https://gromacs.bioexcel.eu/t/how-to-fix-the-error-atomtypes-invalid-order-for-directive-atomtypes/9353/1 "2024-06-10T22:42:10Z")

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GROMACS version:  
GROMACS modification: Yes/No  
Here post your question

Hi,  
I used a CHARMM-GUI ligand modeler and multicomponent assembler to generate a system consisting of one 4- charged EDTA ion, four Ca2+ ions, four Cl- ions, and solvated by water molecules. Since I couldn’t get the final file from the multicomponent assembler formatted in GROMACS, I combined all forcefields (4- charged EDTA ion, Ca2+ ions, Cl- ions, and tip3p) and put them together in a .itp file named “charmm36.itp”.

However, I still get an error of ‘[atomtypes]’ Invalid order for directive atomtypes.

I attached the topol.top file as a reference.

[topol.top](https://gromacs.bioexcel.eu/uploads/short-url/lUkFptttEkcLELnA0RRqN7ylxwG.top) (776 Bytes)

Thanks in advance.

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<div class="post-metadata">

**Author:** ![MagnusL](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/magnusl/32/2380_2.png) [@MagnusL](https://gromacs.bioexcel.eu/u/MagnusL)\
**Post date:** [June 13, 2024, 12:47pm UTC](https://gromacs.bioexcel.eu/t/how-to-fix-the-error-atomtypes-invalid-order-for-directive-atomtypes/9353/2 "2024-06-13T12:47:45Z")

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If you search for the same error or look in the related threads below, you will find more help. The issue is that there may not be any `[atomtypes]` after the first `[moleculetype]` entry in the topology. From your `topol.top` it is not possible to see if there are any `[atomtypes]` sections in the included itp files (except `charmm36.itp`), but I suppose that there are.

But I admit it looks a bit strange, because even in the `IEDTA.itp` file it would be fine with an `[atomtypes]` section and for tip3p and the ions it should not be needed.