Can the Multireference and Single-Reference Density Functional Theory Describe the Chemiluminescent Decomposition of 1,2-Dioxetanes?
Year: 2026
Type: article
Abstract: Multireference DFT and spin-flip (SF) scheme based single-reference DFT methods offer a cost-effective strategy for multireference systems like biradicals. However, their accuracy for modeling chemiluminescent processes—particularly those involving O–O biradical and electron-transfer (ET) character during bond breaking—remains inadequately established. This work assesses the performance of these methods in calculating the potential energy curves (PECs) for both uncatalyzed and ET-catalyzed decomposition of 1,2-dioxetane derivatives. The computations showed that both multireference and single-reference DFT methods can be applied for the qualitative modeling of 1,2-dioxetane chemiluminescence, providing reasonable descriptions of the ground-state reaction pathway and $S_0/S_1$ surface crossings. However, current single-reference methods suffer from more pronounced quantitative errors due to the absence of specific key electronic configurations. For uncatalyzed decomposition of 1,2-dioxetane, this discrepancy arises in single-reference DFT because the O–O biradical system involves additional near-degenerate non-bonding occupied orbitals. The crucial configurations associated with these orbital pairs cannot be captured by the current spin-flip (SF) methodology. For the ET-catalyzed reaction, the ET process alters the singly occupied orbitals in the ground-state reference, leading to two distinct triplet reference states employed as candidates in the SF schemes. The two triplet reference states cannot be included simultaneously, preventing these configurationally important states from coexisting in the wavefunction and thereby introducing substantial errors like overestimation of energy barrier or the discontinuity of PECs. Thus, the single-reference DFT requires rigorous validation and testing when applied to investigate, especially those energy-insensitive task or simulations involved higher excited states.
Authors: Yang-He Liu, Zi-Qi Zhang, Ling Yue
Institution: Xi'an Jiaotong University
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7162018963