Rotated-Frame Determinant Discovery for Ground- and Excited-State Quantum Selected Configuration Interaction

arXiv:2611.05941v1 Announce Type: new Abstract: Quantum Selected Configuration Interaction (QSCI) constructs a variational determinant space from measurements of a prepared electronic state, but finite-shot sampling can repeatedly observe high-probability determinants, limiting efficient discovery of configurations important for an accurate selected-CI description. We introduce rotate--sample--unrotate (RSU) determinant discovery, in which the same state is sampled in complementary orbital frames and the observed rotated determinants generate a finite set of candidates in the canonical basis. The Hamiltonian is then diagonalized in an orthonormal selected-CI space without enumerating the full determinant space.