Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, 35131, Padova, Italy.
School of Chemical Engineering and Analytical Science, University of Manchester, Manchester, UK.
Nat Commun. 2022 Feb 10;13(1):813. doi: 10.1038/s41467-022-28461-y.
Molecular forces induced by optical excitations are connected to a wide range of phenomena, from chemical bond dissociation to intricate biological processes that underpin vision. Commonly, the description of optical excitations requires the solution of computationally demanding electronic Bethe-Salpeter equation (BSE). However, when studying non-covalent interactions in large-scale systems, more efficient methods are desirable. Here we introduce an effective approach based on coupled quantum Drude oscillators (cQDO) as represented by the many-body dispersion model. We find that the cQDO Hamiltonian yields semi-quantitative agreement with BSE calculations and that both attractive and repulsive optical van der Waals (vdW) forces can be induced by light. These optical-vdW interactions dominate over vdW dispersion in the long-distance regime, showing a complexity that grows with system size. Evidence of highly non-local forces in the human formaldehyde dehydrogenase 1MC5 protein suggests the ability to selectively activate collective molecular vibrations by photoabsorption, in agreement with recent experiments.
光激发引起的分子力与广泛的现象相关联，从化学键的解离到支持视觉的复杂生物过程。通常，光激发的描述需要求解计算要求高的电子 Bethe-Salpeter 方程 (BSE)。然而，在研究大规模系统中的非共价相互作用时，需要更有效的方法。在这里，我们引入了一种基于耦合量子 Drude 振荡器 (cQDO) 的有效方法，其表示为多体色散模型。我们发现，cQDO 哈密顿量与 BSE 计算结果具有半定量的一致性，并且可以用光诱导出吸引和排斥的光学范德华 (vdW) 力。这些光-vdW 相互作用在长程范围内主导了 vdW 色散，表现出随系统尺寸增长的复杂性。在人类甲醛脱氢酶 1MC5 蛋白中存在高度非局部力的证据表明，通过光吸收选择性地激活集体分子振动的能力，这与最近的实验结果一致。
