{"paper":{"title":"PACSim: A Flexible Simulation Framework for Polymer-Attenuated Coulombic Self-Assembly","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"PACSim is an open-source molecular dynamics framework for simulating polymer-attenuated Coulombic self-assembly of colloids.","cross_cats":["cond-mat.stat-mech","physics.chem-ph"],"primary_cat":"cond-mat.soft","authors_text":"Glen M. Hocky, John P. Marquardt, Michael S. Chen, Nicole Smina, Philipp H\\\"ollmer, Stefano Sacanna, Steven van Kesteren","submitted_at":"2026-05-13T01:29:06Z","abstract_excerpt":"Polymer-Attenuated Coulombic Self-Assembly (PACS) is a flexible experimental approach for generating crystals from simple colloidal building blocks. The central components are charged spherical particles coated with a polymer brush that prevents irreversible aggregation. Whether oppositely charged colloids crystallize, and which structures they form, depends on several factors, including colloid concentration, charge, and size, as well as the salt concentration of the solution. Molecular dynamics (MD) simulations are a powerful tool for predicting the outcomes of PACS assembly experiments and "},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Here, we present an open-source simulation framework, PACSim, that enables MD simulation studies of assembly by PACS across a range of experimentally relevant scenarios.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The assumption that the interaction potentials implemented in PACSim faithfully capture the polymer-brush attenuation and Coulombic forces present in real PACS experiments, without post-hoc adjustments.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"PACSim is a new open-source MD simulation framework on OpenMM for studying polymer-attenuated Coulombic self-assembly of colloids.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"PACSim is an open-source molecular dynamics framework for simulating polymer-attenuated Coulombic self-assembly of colloids.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"ee3e72cb032d5fbb6bafb444b653de7408e044ff9e261426912925a5117ae562"},"source":{"id":"2605.12870","kind":"arxiv","version":1},"verdict":{"id":"20acb5d4-4580-498a-87a0-0b82d5e21da3","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T18:50:55.476502Z","strongest_claim":"Here, we present an open-source simulation framework, PACSim, that enables MD simulation studies of assembly by PACS across a range of experimentally relevant scenarios.","one_line_summary":"PACSim is a new open-source MD simulation framework on OpenMM for studying polymer-attenuated Coulombic self-assembly of colloids.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The assumption that the interaction potentials implemented in PACSim faithfully capture the polymer-brush attenuation and Coulombic forces present in real PACS experiments, without post-hoc adjustments.","pith_extraction_headline":"PACSim is an open-source molecular dynamics framework for simulating polymer-attenuated Coulombic self-assembly of colloids."},"references":{"count":55,"sample":[{"doi":"","year":2001,"title":"U. Gasser, E. R. Weeks, A. Schofield, P. N. Pusey, and D. A. Weitz, Real-space imaging of nucleation and growth in colloidal crystallization, Science 292, 258 (2001)","work_id":"d759521a-a9da-46fd-ab60-f18e98b079e2","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2021,"title":"T. Hueckel, G. M. Hocky, and S. Sacanna, Total synthesis of colloidal matter, Nat. Rev. Mater. 6, 1053 (2021)","work_id":"838e8fba-bd31-4fa7-a92e-a99d039c4c21","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2024,"title":"S. Zang, A. W. Hauser, S. Paul, G. M. Hocky, and S. Sacanna, Enabling three-dimensional real-space analy- sis of ionic colloidal crystallization, Nat. Mater. 23, 1131 (2024)","work_id":"26f3f9eb-e722-4de2-9b8b-c4e3db44a825","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2017,"title":"´E. Ducrot, M. He, G.-R. Yi, and D. J. Pine, Colloidal al- loys with preassembled clusters and spheres, Nat. Mater. 16, 652 (2017)","work_id":"38f2ebdb-e4ec-4a81-8b39-69a138c0a295","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2017,"title":"Y. Wang, I. C. Jenkins, J. T. McGinley, T. Sinno, and J. C. Crocker, Colloidal crystals with diamond symmetry at optical lengthscales, Nat. Commun. 8, 14173 (2017)","work_id":"2b6eb08c-63d8-43f5-9367-964515eccbd6","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":55,"snapshot_sha256":"99bff368486b005f6821a82139e0c218432659b49c4ad2cdf16676fe25738788","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}