Hi, good question. I believe all you’ll need to put is
And it will figure out the type for you.
We are working on an improved interface where you can also leave off the type for ITensor related types but right now it’s required. For some more information, when you are writing and reading native Julia types like floats, the write and read functions are just those from the HDF5.jl library. But we have created overloads of write and read for writing and reading ITensor types.