{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:MQ2H6WKL2YLSJSRA7QLY7CSVA6","short_pith_number":"pith:MQ2H6WKL","canonical_record":{"source":{"id":"1903.10204","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2019-03-25T09:40:10Z","cross_cats_sorted":[],"title_canon_sha256":"ac883926d3e08fd790a7c83467bd24a7f915ba0ceb67d10c015970f2294d9a38","abstract_canon_sha256":"c3ce08c29acf519e645a2fcc0590319f1c51c7aee6091f042bb89bb9b734ca85"},"schema_version":"1.0"},"canonical_sha256":"64347f594bd61724ca20fc178f8a5507873675e2b5271aa57b03f6480e5f606d","source":{"kind":"arxiv","id":"1903.10204","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.10204","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"arxiv_version","alias_value":"1903.10204v1","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.10204","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"pith_short_12","alias_value":"MQ2H6WKL2YLS","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"pith_short_16","alias_value":"MQ2H6WKL2YLSJSRA","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"pith_short_8","alias_value":"MQ2H6WKL","created_at":"2026-07-05T03:18:23Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:MQ2H6WKL2YLSJSRA7QLY7CSVA6","target":"record","payload":{"canonical_record":{"source":{"id":"1903.10204","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2019-03-25T09:40:10Z","cross_cats_sorted":[],"title_canon_sha256":"ac883926d3e08fd790a7c83467bd24a7f915ba0ceb67d10c015970f2294d9a38","abstract_canon_sha256":"c3ce08c29acf519e645a2fcc0590319f1c51c7aee6091f042bb89bb9b734ca85"},"schema_version":"1.0"},"canonical_sha256":"64347f594bd61724ca20fc178f8a5507873675e2b5271aa57b03f6480e5f606d","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T03:18:23.331473Z","signature_b64":"ybAlOAWRiuE3b+/hu6MAYYvEQSbA0fd4t0/DcjLdZ1SOAFv7/J8Kyi/rVJE5xfJ5440gRgkLjiJVySHAMuTOCw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"64347f594bd61724ca20fc178f8a5507873675e2b5271aa57b03f6480e5f606d","last_reissued_at":"2026-07-05T03:18:23.331058Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T03:18:23.331058Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1903.10204","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T03:18:23Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"TyVtpU9NLMeUiEfRWYB2nXBu/F90fIITxSw9R89k6er4ajGvGa9YzefeUsq+O+dU/2W7cV0sOaIX8slw8lk5BA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-06T14:59:21.368963Z"},"content_sha256":"29fa9147937d97db7744ff96612611049a9ecb9db69f082139c4aab419cafd4e","schema_version":"1.0","event_id":"sha256:29fa9147937d97db7744ff96612611049a9ecb9db69f082139c4aab419cafd4e"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:MQ2H6WKL2YLSJSRA7QLY7CSVA6","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"On the role of the electron-phonon interaction in the temperature dependence of the gap of lead halide perovskites","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cond-mat.mtrl-sci","authors_text":"08010 Barcelona, 08193 Bellaterra, (2) Dept. of Chemistry \\& Centre for Sustainable Chemical Technologies, 3) ((1) Institut de Ci\\`encia de Materials de Barcelona (ICMAB-CSIC), (3) ICREA, A. Francisco-L\\'opez (1), A. R.~Go\\~ni (1, Bath BA2 7AY, B. Charles (2), Campus UAB, Claverton Down, M. Campoy-Quiles (1), M. Garriga (1), M. I. Alonso (1), M. T. Weller (2), O. J. Weber (2), Passeig Llu\\'is Companys 23, Spain, Spain), UK, University of Bath","submitted_at":"2019-03-25T09:40:10Z","abstract_excerpt":"Lead halide perovskites are causing a change of paradigm in photovoltaics. Among other peculiarities, these perovskites exhibit an atypical temperature dependence of the fundamental optical gap: It decreases in energy with decreasing temperature. So far reports ascribe such a behavior to a particularly strong electron-phonon renormalization of the band gap, neglecting completely contributions from thermal expansion effects. However, high pressure experiments performed, for instance, on the archetypal perovskite MAPbI$_3$, where MA stands for methylammonium, yield a negative pressure coefficien"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.10204","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/1903.10204/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T03:18:23Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"j2CzsXZ8w6bieMdQFm6xLeobWh+1Hv8BjUYHjHdCoK/gfNaDPwqLuAfEzYKkL8EDcPDkxmx0oSlhxa2gKe5+BQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-06T14:59:21.369354Z"},"content_sha256":"3a4322ca95c18deaea9ecd885f30cb7c8ef43900b9af55a3f8e5ff189a976895","schema_version":"1.0","event_id":"sha256:3a4322ca95c18deaea9ecd885f30cb7c8ef43900b9af55a3f8e5ff189a976895"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/MQ2H6WKL2YLSJSRA7QLY7CSVA6/bundle.json","state_url":"https://pith.science/pith/MQ2H6WKL2YLSJSRA7QLY7CSVA6/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/MQ2H6WKL2YLSJSRA7QLY7CSVA6/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-07-06T14:59:21Z","links":{"resolver":"https://pith.science/pith/MQ2H6WKL2YLSJSRA7QLY7CSVA6","bundle":"https://pith.science/pith/MQ2H6WKL2YLSJSRA7QLY7CSVA6/bundle.json","state":"https://pith.science/pith/MQ2H6WKL2YLSJSRA7QLY7CSVA6/state.json","well_known_bundle":"https://pith.science/.well-known/pith/MQ2H6WKL2YLSJSRA7QLY7CSVA6/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:MQ2H6WKL2YLSJSRA7QLY7CSVA6","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"c3ce08c29acf519e645a2fcc0590319f1c51c7aee6091f042bb89bb9b734ca85","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2019-03-25T09:40:10Z","title_canon_sha256":"ac883926d3e08fd790a7c83467bd24a7f915ba0ceb67d10c015970f2294d9a38"},"schema_version":"1.0","source":{"id":"1903.10204","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.10204","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"arxiv_version","alias_value":"1903.10204v1","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.10204","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"pith_short_12","alias_value":"MQ2H6WKL2YLS","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"pith_short_16","alias_value":"MQ2H6WKL2YLSJSRA","created_at":"2026-07-05T03:18:23Z"},{"alias_kind":"pith_short_8","alias_value":"MQ2H6WKL","created_at":"2026-07-05T03:18:23Z"}],"graph_snapshots":[{"event_id":"sha256:3a4322ca95c18deaea9ecd885f30cb7c8ef43900b9af55a3f8e5ff189a976895","target":"graph","created_at":"2026-07-05T03:18:23Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/1903.10204/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Lead halide perovskites are causing a change of paradigm in photovoltaics. Among other peculiarities, these perovskites exhibit an atypical temperature dependence of the fundamental optical gap: It decreases in energy with decreasing temperature. So far reports ascribe such a behavior to a particularly strong electron-phonon renormalization of the band gap, neglecting completely contributions from thermal expansion effects. However, high pressure experiments performed, for instance, on the archetypal perovskite MAPbI$_3$, where MA stands for methylammonium, yield a negative pressure coefficien","authors_text":"08010 Barcelona, 08193 Bellaterra, (2) Dept. of Chemistry \\& Centre for Sustainable Chemical Technologies, 3) ((1) Institut de Ci\\`encia de Materials de Barcelona (ICMAB-CSIC), (3) ICREA, A. Francisco-L\\'opez (1), A. R.~Go\\~ni (1, Bath BA2 7AY, B. Charles (2), Campus UAB, Claverton Down, M. Campoy-Quiles (1), M. Garriga (1), M. I. Alonso (1), M. T. Weller (2), O. J. Weber (2), Passeig Llu\\'is Companys 23, Spain, Spain), UK, University of Bath","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2019-03-25T09:40:10Z","title":"On the role of the electron-phonon interaction in the temperature dependence of the gap of lead halide perovskites"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.10204","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:29fa9147937d97db7744ff96612611049a9ecb9db69f082139c4aab419cafd4e","target":"record","created_at":"2026-07-05T03:18:23Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"c3ce08c29acf519e645a2fcc0590319f1c51c7aee6091f042bb89bb9b734ca85","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2019-03-25T09:40:10Z","title_canon_sha256":"ac883926d3e08fd790a7c83467bd24a7f915ba0ceb67d10c015970f2294d9a38"},"schema_version":"1.0","source":{"id":"1903.10204","kind":"arxiv","version":1}},"canonical_sha256":"64347f594bd61724ca20fc178f8a5507873675e2b5271aa57b03f6480e5f606d","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"64347f594bd61724ca20fc178f8a5507873675e2b5271aa57b03f6480e5f606d","first_computed_at":"2026-07-05T03:18:23.331058Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T03:18:23.331058Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"ybAlOAWRiuE3b+/hu6MAYYvEQSbA0fd4t0/DcjLdZ1SOAFv7/J8Kyi/rVJE5xfJ5440gRgkLjiJVySHAMuTOCw==","signature_status":"signed_v1","signed_at":"2026-07-05T03:18:23.331473Z","signed_message":"canonical_sha256_bytes"},"source_id":"1903.10204","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:29fa9147937d97db7744ff96612611049a9ecb9db69f082139c4aab419cafd4e","sha256:3a4322ca95c18deaea9ecd885f30cb7c8ef43900b9af55a3f8e5ff189a976895"],"state_sha256":"0175c270082add3d2b2c9e40313128f043de3249abb66c80188de2fa56e058be"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"1TaEjmIg4w14ECZQpTHmPu1apwvQVtX4h1UZbL7n5Z0E9WlAYtO4onQdbrN0JqZQGxb/YPMHhEAn5vOwmFwnAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-06T14:59:21.371751Z","bundle_sha256":"b8ad7f4f787d4b515fc9c301d8d7b3f1df67ef1c56201be400a73b1917a11087"}}