Pauline Ollitrault

Slow behaviour of functools reduce() in VibrationalOp

2

### What is the expected enhancement? This line: https://github.com/Qiskit/qiskit-nature/blob/76c9f976c08ba49c6397a40cc138e62a9f827b7a/qiskit_nature/operators/second_quantization/vibrational_op.py#L162 is too slow to treat large system sizes.

COBRA: commutator algebra for efficient excited state calculation

7

# Abstract Computing the excited states of molecules is essential to the understanding of photochemical reactions and in turn to the design of new materials for e.g. solar cells. Last...