{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T03:35:41Z","timestamp":1769657741754,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:00:00Z","timestamp":1769558400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy (DOE) Office of Basic Energy Sciences","doi-asserted-by":"publisher","award":["DE-SC0026309"],"award-info":[{"award-number":["DE-SC0026309"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>We present hybrid quantum\u2013classical algorithms to compute time-dependent M\u00f8ller wavepacket correlation functions via digital quantum simulation. Reactant and product channel wavepackets are encoded as qubit states, evolved under a discretized molecular Hamiltonian, and their correlation is reconstructed using both a modified Hadamard test and a multi-fidelity estimation (MFE) protocol. The method is applied to the collinear H + H2 exchange reaction on a London\u2013Eyring\u2013Polanyi\u2013Sato potential energy surface. Quantum-estimated correlation functions show quantitative agreement with high-resolution classical wavepacket simulations across the full time domain, reproducing both short-time scattering peaks and long-time oscillatory dynamics. The ancilla-free MFE protocol achieves matching results with reduced circuit depth. These results provide a proof of principle that digital quantum circuits can be used to accurately calculate the wavepacket correlation functions for a benchmark chemical reaction system.<\/jats:p>","DOI":"10.3390\/e28020144","type":"journal-article","created":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T15:04:46Z","timestamp":1769612686000},"page":"144","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Digital Quantum Simulation of Wavepacket Correlations in a Chemical Reaction"],"prefix":"10.3390","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7382-6466","authenticated-orcid":false,"given":"Shah Ishmam","family":"Mohtashim","sequence":"first","affiliation":[{"name":"Department of Chemistry, North Carolina State University, Raleigh, NC 27695, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0574-5346","authenticated-orcid":false,"given":"Sabre","family":"Kais","sequence":"additional","affiliation":[{"name":"Department of Chemistry, North Carolina State University, Raleigh, NC 27695, USA"},{"name":"Department of Electrical & Computer Engineering, North Carolina State University, Raleigh, NC 27695, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2087","DOI":"10.1021\/j100319a003","article-title":"Time-dependent quantum-mechanical methods for molecular dynamics","volume":"92","author":"Kosloff","year":"1988","journal-title":"J. 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