# Cannot sweep the Material Properties?

#1

The Parameter Sweep cannot directly access the Material Properties by default. This post has some tips how to sweep the Material Properties using the Parameter Sweep.

## Using the Setup tab of a group (Analysis Group, Structure Group, Model)

We are going to use the Graphene material as an example to sweep the “chemical potential”.

Set up the User Properties in the Variables tab

In the Script tab, set the Material Properties using the setmaterial command
setmaterial("graphene_material","chemical potential (eV)",voltage);

Now in the Edit Parameter Sweep window, users can access the “voltage” variable to sweep the “chemical potential” of the Graphene material.

This procedure should be applicable to other materials, include plugins. Example file: material_parameter_sweep.fsp (232.8 KB)

Note: users may have to pay attention to the material fitting as the properties may significantly affect the fit. Please refer to this KB article for more info about modifying the material fits.

## Alternatives

The Parameter Sweep can access the Properties of a structure. Once a structure is created, users can pick some existing materials from the Material Database for the Parameter Sweep. In this case, users will have to create multiple materials with the corresponding Material Properties pre-assigned. In most cases, the above method using the Setup tab of Group might be an easier way.

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