  We improve the methodology to construct a complete active space-configuration
interaction (CAS-CI) expansion for density-matrix renormalization group (DMRG)
wave function using matrix-product state representation, inspired by the
sampling-reconstructed CAS [SR-CAS, Boguslawski et al, J. Chem. Phys. 2011,
134, 224101] algorithm. In our scheme, a genetic algorithm, in which the
"crossover" and "mutation" process can be optimized based on quantum
information theory, is employed when reconstructing the CASCI-type wave
function in the Hilbert space. Test analysis results for the ground and excited
state wave functions of conjugated molecules and transition metal compounds
illustrate that our scheme is very efficient for searching the most important
CI expansions in large active spaces.
