Limits RegistryPUBLIC RECORD
Limits RegistryIn 2005, Philip Power's group at the University of California, Davis, reported Ar'CrCrAr', a dichromium compound with bulky terphenyl ligands containing a Cr–Cr quintuple bond (σ2π4δ4, ten bonding electrons) only about 1.835 Å long. Higher bond orders (sextuple) are known only in gas-phase diatomics such as Mo2 and W2.
The question, scope, and sources behind this Registry record.
In 2005, Philip Power's group at the University of California, Davis, reported Ar'CrCrAr', a dichromium compound with bulky terphenyl ligands containing a Cr–Cr quintuple bond (σ2π4δ4, ten bonding electrons) only about 1.835 Å long. Higher bond orders (sextuple) are known only in gas-phase diatomics such as Mo2 and W2.
The highest bond order experimentally established between two atoms in a compound stable enough to isolate and characterise.
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Current frontiers derived from accepted Claims.
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The frontier as it changed over time.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-HIGHEST-BOND-ORDER-STABLE-COMPOUND
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Limits Registry. LR-HIGHEST-BOND-ORDER-STABLE-COMPOUND. Highest bond order in an isolable compound (first quintuple bond). 2026.