Fig. 5: Comparison of ansätze for the ground and excited state calculations of ethylene. | npj Computational Materials

Fig. 5: Comparison of ansätze for the ground and excited state calculations of ethylene.

From: Excited state calculations using variational quantum eigensolver with spin-restricted ansätze and automatically-adjusted constraints

Fig. 5

Energy deviations ΔE (in kcal mol−1) from the exact values for S0 at the FC (a), S1 at the FC (b), S0 at the CI (c), and S1 at the CI (d) were calculated using the SA-CASSCF method. The errors in energy obtained by the statevector and noisy-QASM simulators are shown in red and blue, respectively. The results labeled with an ‘*’ indicate that the maximum number of orbital rotations was reached. The parameters were β = 1 for all the ansätze, γ = 1 for the heuristic ansätze. Detailed values are shown in Supplementary Table 2.

Back to article page