{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:XU5MFO42RRTVH2H4K36EL323SC","short_pith_number":"pith:XU5MFO42","canonical_record":{"source":{"id":"1811.00969","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2018-11-02T16:34:13Z","cross_cats_sorted":[],"title_canon_sha256":"b9c2c4649383e0afcff20e9a278a5a518c5d94ed3a82698b23877ada57a25792","abstract_canon_sha256":"4e7e3d27959f956047a09900fc443d70dfc629f45357bc518704e25c02207405"},"schema_version":"1.0"},"canonical_sha256":"bd3ac2bb9a8c6753e8fc56fc45ef5b90af309d348070293fb8cb2bb99923f356","source":{"kind":"arxiv","id":"1811.00969","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1811.00969","created_at":"2026-05-17T23:52:04Z"},{"alias_kind":"arxiv_version","alias_value":"1811.00969v1","created_at":"2026-05-17T23:52:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1811.00969","created_at":"2026-05-17T23:52:04Z"},{"alias_kind":"pith_short_12","alias_value":"XU5MFO42RRTV","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"XU5MFO42RRTVH2H4","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"XU5MFO42","created_at":"2026-05-18T12:33:01Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:XU5MFO42RRTVH2H4K36EL323SC","target":"record","payload":{"canonical_record":{"source":{"id":"1811.00969","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2018-11-02T16:34:13Z","cross_cats_sorted":[],"title_canon_sha256":"b9c2c4649383e0afcff20e9a278a5a518c5d94ed3a82698b23877ada57a25792","abstract_canon_sha256":"4e7e3d27959f956047a09900fc443d70dfc629f45357bc518704e25c02207405"},"schema_version":"1.0"},"canonical_sha256":"bd3ac2bb9a8c6753e8fc56fc45ef5b90af309d348070293fb8cb2bb99923f356","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:52:04.509033Z","signature_b64":"9vO01DcCE0LW9xDmsq8MgyRRqpX1A48ATU1Q/DtDKS3c6bz3TQkSveYeBdZkK6nA4ZSMQnqYXXwNd7L6okKODg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"bd3ac2bb9a8c6753e8fc56fc45ef5b90af309d348070293fb8cb2bb99923f356","last_reissued_at":"2026-05-17T23:52:04.508475Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:52:04.508475Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1811.00969","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":"2026-05-17T23:52:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"EAxqzNdLS40MbAwiT8U5VmG0LUZexg+iF6weevwx4aYzRvfOaMr41CzCdVq3JnSaOak+DV9hJNTg5pIp6AwpAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T02:39:32.190736Z"},"content_sha256":"f08d32032e04d605bddf408561e0ff5f8dec8e5355b9f335d2a2ed2d317faa41","schema_version":"1.0","event_id":"sha256:f08d32032e04d605bddf408561e0ff5f8dec8e5355b9f335d2a2ed2d317faa41"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:XU5MFO42RRTVH2H4K36EL323SC","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Prediction for the singlet-triplet excitation energy for the spinel MgTi$_2$O$_4$ using first-principles diffusion Monte Carlo","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cond-mat.str-el","authors_text":"Brian Busemeyer, Gregory J. MacDougall, Lucas K. Wagner","submitted_at":"2018-11-02T16:34:13Z","abstract_excerpt":"The spinel, MgTi$_2$O$_4$, undergoes a transition into a dimerized state at low temperatures that is expected to be a spin singlet. However, no signature of a singlet-triplet transition has been discovered, in part due to the difficulty of predicting the energy of the transition from theory. We find that the dimers of MgTi$_2$O$_4$ can be described by a Heisenberg model with very small interactions between different dimers. Using high-accuracy first-principles quantum Monte Carlo combined with a novel model-fitting approach, we predict the singlet-triplet gap of these dimers to be 350(50) meV,"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1811.00969","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":""},"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":"2026-05-17T23:52:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"v1f84E5Xcx1W8JHG4hVWOLDoBSHTeSBkhlG62Wn3864OaMHV8mEHEC+LVir29ot+CXdDOymPp+5MC7Wp6fMJDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T02:39:32.191083Z"},"content_sha256":"2318af0da8a2253c373170973e1804c75719e8ce39dbde193b9d1a6c6b1ed05e","schema_version":"1.0","event_id":"sha256:2318af0da8a2253c373170973e1804c75719e8ce39dbde193b9d1a6c6b1ed05e"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/XU5MFO42RRTVH2H4K36EL323SC/bundle.json","state_url":"https://pith.science/pith/XU5MFO42RRTVH2H4K36EL323SC/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/XU5MFO42RRTVH2H4K36EL323SC/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":"2026-06-03T02:39:32Z","links":{"resolver":"https://pith.science/pith/XU5MFO42RRTVH2H4K36EL323SC","bundle":"https://pith.science/pith/XU5MFO42RRTVH2H4K36EL323SC/bundle.json","state":"https://pith.science/pith/XU5MFO42RRTVH2H4K36EL323SC/state.json","well_known_bundle":"https://pith.science/.well-known/pith/XU5MFO42RRTVH2H4K36EL323SC/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:XU5MFO42RRTVH2H4K36EL323SC","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":"4e7e3d27959f956047a09900fc443d70dfc629f45357bc518704e25c02207405","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2018-11-02T16:34:13Z","title_canon_sha256":"b9c2c4649383e0afcff20e9a278a5a518c5d94ed3a82698b23877ada57a25792"},"schema_version":"1.0","source":{"id":"1811.00969","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1811.00969","created_at":"2026-05-17T23:52:04Z"},{"alias_kind":"arxiv_version","alias_value":"1811.00969v1","created_at":"2026-05-17T23:52:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1811.00969","created_at":"2026-05-17T23:52:04Z"},{"alias_kind":"pith_short_12","alias_value":"XU5MFO42RRTV","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"XU5MFO42RRTVH2H4","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"XU5MFO42","created_at":"2026-05-18T12:33:01Z"}],"graph_snapshots":[{"event_id":"sha256:2318af0da8a2253c373170973e1804c75719e8ce39dbde193b9d1a6c6b1ed05e","target":"graph","created_at":"2026-05-17T23:52:04Z","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"},"paper":{"abstract_excerpt":"The spinel, MgTi$_2$O$_4$, undergoes a transition into a dimerized state at low temperatures that is expected to be a spin singlet. However, no signature of a singlet-triplet transition has been discovered, in part due to the difficulty of predicting the energy of the transition from theory. We find that the dimers of MgTi$_2$O$_4$ can be described by a Heisenberg model with very small interactions between different dimers. Using high-accuracy first-principles quantum Monte Carlo combined with a novel model-fitting approach, we predict the singlet-triplet gap of these dimers to be 350(50) meV,","authors_text":"Brian Busemeyer, Gregory J. MacDougall, Lucas K. Wagner","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2018-11-02T16:34:13Z","title":"Prediction for the singlet-triplet excitation energy for the spinel MgTi$_2$O$_4$ using first-principles diffusion Monte Carlo"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1811.00969","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:f08d32032e04d605bddf408561e0ff5f8dec8e5355b9f335d2a2ed2d317faa41","target":"record","created_at":"2026-05-17T23:52:04Z","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":"4e7e3d27959f956047a09900fc443d70dfc629f45357bc518704e25c02207405","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2018-11-02T16:34:13Z","title_canon_sha256":"b9c2c4649383e0afcff20e9a278a5a518c5d94ed3a82698b23877ada57a25792"},"schema_version":"1.0","source":{"id":"1811.00969","kind":"arxiv","version":1}},"canonical_sha256":"bd3ac2bb9a8c6753e8fc56fc45ef5b90af309d348070293fb8cb2bb99923f356","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"bd3ac2bb9a8c6753e8fc56fc45ef5b90af309d348070293fb8cb2bb99923f356","first_computed_at":"2026-05-17T23:52:04.508475Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:52:04.508475Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"9vO01DcCE0LW9xDmsq8MgyRRqpX1A48ATU1Q/DtDKS3c6bz3TQkSveYeBdZkK6nA4ZSMQnqYXXwNd7L6okKODg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:52:04.509033Z","signed_message":"canonical_sha256_bytes"},"source_id":"1811.00969","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f08d32032e04d605bddf408561e0ff5f8dec8e5355b9f335d2a2ed2d317faa41","sha256:2318af0da8a2253c373170973e1804c75719e8ce39dbde193b9d1a6c6b1ed05e"],"state_sha256":"99bfe807079dc9a50ab0c85f7c459c827f20142fbae5f65885f685ea6d4be2f5"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"RAaKg1y+a+oVLjSPuQeAUi2UVnSmUVmCLv6PGdtCi2feo7b5WZyD9yrlNSMG5Mxg/WGmq7Ip2iKzuaIW24dYBg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-03T02:39:32.193075Z","bundle_sha256":"665039d499c1664186a46a38ca1ca2de910e57847391a018a296ba858e5ebb8f"}}