{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T18:24:56Z","timestamp":1787163896004,"version":"build-2736575974"},"reference-count":44,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2017,5,11]],"date-time":"2017-05-11T00:00:00Z","timestamp":1494460800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["GM59796"],"award-info":[{"award-number":["GM59796"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["GM11364"],"award-info":[{"award-number":["GM11364"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000928","name":"Welch Foundation","doi-asserted-by":"publisher","award":["F-1896"],"award-info":[{"award-number":["F-1896"]}],"id":[{"id":"10.13039\/100000928","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Reaction coordinates are vital tools for qualitative and quantitative analysis of molecular processes. They provide a simple picture of reaction progress and essential input for calculations of free energies and rates. Iso-committor surfaces are considered the optimal reaction coordinate. We present an algorithm to compute efficiently a sequence of isocommittor surfaces. These surfaces are considered an optimal reaction coordinate. The algorithm analyzes Milestoning results to determine the committor function. It requires only the transition probabilities between the milestones, and not transition times. We discuss the following numerical examples: (i) a transition in the Mueller potential; (ii) a conformational change of a solvated peptide; and (iii) cholesterol aggregation in membranes.<\/jats:p>","DOI":"10.3390\/e19050219","type":"journal-article","created":{"date-parts":[[2017,5,11]],"date-time":"2017-05-11T11:06:46Z","timestamp":1494500806000},"page":"219","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":56,"title":["Calculating Iso-Committor Surfaces as Optimal Reaction Coordinates with Milestoning"],"prefix":"10.3390","volume":"19","author":[{"given":"Ron","family":"Elber","sequence":"first","affiliation":[{"name":"Institute for Computational Engineering and Science, The University of Texas at Austin, Austin, TX 78712, USA"},{"name":"Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan","family":"Bello-Rivas","sequence":"additional","affiliation":[{"name":"Institute for Computational Engineering and Science, The University of Texas at Austin, Austin, TX 78712, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Piao","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alfredo","family":"Cardenas","sequence":"additional","affiliation":[{"name":"Institute for Computational Engineering and Science, The University of Texas at Austin, Austin, TX 78712, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arman","family":"Fathizadeh","sequence":"additional","affiliation":[{"name":"Institute for Computational Engineering and Science, The University of Texas at Austin, Austin, TX 78712, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,5,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1016\/0021-9991(77)90121-8","article-title":"Non-physical sampling distributions in monte-carlo free-energy estimation\u2014Umbrella sampling","volume":"23","author":"Torrie","year":"1977","journal-title":"J. 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