What dominates the error in the CaO diatomic bond energy predicted by various approximate exchange-correlation functionals?

Engineering & Materials Science

• Excitation energy 100%
• Calcium oxide 81%
• Ionization potential 63%
• Positive ions 59%
• Dipole moment 56%
• Electron affinity 46%
• Charge distribution 34%
• Atoms 24%
• Metals 22%
• Electronic states 18%
• Oxygen 9%

Chemical Compounds

• Bond Energy 80%
• Error 53%
• Orbital 51%
• Energy 33%
• Ionization Potential 26%
• Dipole Moment 24%
• Metal Atom 17%
• Cation 15%
• Electron Correlation Energy 11%
• Singlet State 10%
• Triplet State 8%
• Valence 7%
• Electronic State 6%
• Metal Ion 5%
• Dioxygen 4%

Physics & Astronomy

• functionals 66%
• orbitals 23%
• energy 20%
• cations 15%
• dissociation 15%
• ionization potentials 15%
• atomic excitations 13%
• dipole moments 12%
• electron affinity 10%
• charge distribution 9%
• metals 7%
• excitation 6%
• atomic energy levels 5%
• cancellation 4%
• atoms 4%
• valence 3%
• oxygen 2%
• curves 2%
• electronics 2%
• interactions 1%