{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T17:17:47Z","timestamp":1790356667160,"version":"4.1.0"},"reference-count":120,"publisher":"American Chemical Society (ACS)","issue":"14","license":[{"start":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T00:00:00Z","timestamp":1783641600000},"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","doi-asserted-by":"publisher","award":["DE-SC0024532"],"award-info":[{"award-number":["DE-SC0024532"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,7,28]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>We present an efficient implementation of a one-step relativistic second-order multireference perturbation theory based on the multireference driven similarity renormalization group (MR-DSRG) using the exact two-component (X2C) Hamiltonian, which we denote X2C-DSRG-MRPT2. We show that the X2C-DSRG-MRPT2 method can accurately capture spin\u2013orbit coupling (SOC) effects in the electronic structure of strongly correlated systems containing elements across the periodic table. We further demonstrate that the X2C-DSRG-MRPT2 method, through its variational treatment of SOC effects, can yield spin\u2013orbit splittings with mean absolute percentage errors consistently below 7% with respect to experimental values for systems containing up to sixth row elements. With its modest computational scaling (fourth power in system size for the perturbative step) and high accuracy, X2C-DSRG-MRPT2 provides a promising avenue for the routine treatment of relativistic effects in strongly correlated molecular systems.<\/jats:p>","DOI":"10.1021\/acs.jctc.6c00935","type":"journal-article","created":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T20:21:21Z","timestamp":1783714881000},"page":"7230-7248","source":"Crossref","is-referenced-by-count":2,"title":["One-Step Relativistic\nDriven Similarity Renormalization\nGroup Multireference Perturbation Theory"],"prefix":"10.1021","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0399-2968","authenticated-orcid":true,"given":"Zijun","family":"Zhao","sequence":"first","affiliation":[{"name":"Emory University , , , ,","place":["Atlanta, Georgia, United States, 30322"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7917-6652","authenticated-orcid":true,"given":"Francesco A.","family":"Evangelista","sequence":"additional","affiliation":[{"name":"Emory University , , , ,","place":["Atlanta, Georgia, United States, 30322"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,10]]},"reference":[{"key":"2026072808091214000_cit1","doi-asserted-by":"publisher","first-page":"7969","DOI":"10.1021\/acs.jctc.4c00797","article-title":"State Interaction\nfor Relativistic Four-Component Methods: Choose the Right Zeroth-Order\nHamiltonian for Late-Row Elements","volume":"20","author":"Hoyer","year":"2024","journal-title":"J. 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