CartesianIndexNames is an option for FCFAConvert, FCCanonicalizeDummyIndices and other functions. It renames the generic dummy Cartesian indices to the indices in the supplied list.
Overview, FCFAConvert, FCCanonicalizeDummyIndices, CartesianIndexNames.
CLC[i1, i2, i3] CGA[i1, i2, i3]
FCCanonicalizeDummyIndices[%]\overline{\gamma }^{\text{i1}}.\overline{\gamma }^{\text{i2}}.\overline{\gamma }^{\text{i3}} \bar{\epsilon }^{\text{i1}\;\text{i2}\;\text{i3}}
\overline{\gamma }^{\text{FCGV}(\text{ci201})}.\overline{\gamma }^{\text{FCGV}(\text{ci202})}.\overline{\gamma }^{\text{FCGV}(\text{ci203})} \bar{\epsilon }^{\text{FCGV}(\text{ci201})\text{FCGV}(\text{ci202})\text{FCGV}(\text{ci203})}
CLC[i1, i2, i3] CGA[i1, i2, i3]
FCCanonicalizeDummyIndices[%, CartesianIndexNames -> {i, j, k}]\overline{\gamma }^{\text{i1}}.\overline{\gamma }^{\text{i2}}.\overline{\gamma }^{\text{i3}} \bar{\epsilon }^{\text{i1}\;\text{i2}\;\text{i3}}
\overline{\gamma }^i.\overline{\gamma }^j.\overline{\gamma }^k \bar{\epsilon }^{ijk}