# Time Evolving Kagome Heisenberg AF Ground State

I'm trying to perform real-time evolution of the Heisenberg anti-ferromagnet on a Kagome lattice using fitApplyMPO. When I try to do this with a spin-half chain I don't get any errors. For the kagome lattice, the Hamiltonian I generate gives me a reasonable ground state so I think the problem isn't in the MPO itself. Furthermore, I also don't get errors (even in debug mode) when I do

auto expH = toExpH<ITensor>(aH, tau*Cplx_i);


The problem only occurs during this line:

psi = fitApplyMPO(psi, expH, args);


This is the error I get:

terminate called after throwing an instance of 'std::bad_alloc'
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