Limits RegistryPUBLIC RECORD
Limits RegistryIn 2018, Takanori Suzuki, Yusuke Ishigaki and colleagues at Hokkaido University reported a hexaphenylethane-type hydrocarbon with a C–C single bond 1.806 Å long — exceeding a previously predicted ~1.803 Å stability limit. A typical C–C single bond is 1.54 Å; the molecule's 'core-shell' design used a rigid outer framework to stabilise the stretched core bond.
The question, scope, and sources behind this Registry record.
In 2018, Takanori Suzuki, Yusuke Ishigaki and colleagues at Hokkaido University reported a hexaphenylethane-type hydrocarbon with a C–C single bond 1.806 Å long — exceeding a previously predicted ~1.803 Å stability limit. A typical C–C single bond is 1.54 Å; the molecule's 'core-shell' design used a rigid outer framework to stabilise the stretched core bond.
The longest experimentally measured covalent single bond between two carbon atoms in a stable, isolable compound.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-LONGEST-CARBON-CARBON-SINGLE-BOND
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Limits Registry. LR-LONGEST-CARBON-CARBON-SINGLE-BOND. Longest carbon–carbon single bond. 2026.