Abstract
Density functional theory (DFT) calculations have been carried out on four novel dicoordinated lead compounds PbL2 where L is an N-heterocyclic ylidene or a five-membered cyclic ylidene (1Pb, 2Pb, 4Pb, 5Pb) and for a plumbylene-coordinated carbone CL2 (3Pb). The theoretically predicted equilibrium geometries and the first and second proton affinities of 1Pb-5Pb are reported. Geometry optimizations have also been carried out for the complexes with one and two BH3 ligands 1Pb(BH3)-5Pb(BH3) and 1Pb(BH3)2-5Pb(BH3)2, and for the transition metal complexes 1PbW(CO)5-5PbW(CO)5 and 1PbNi(CO)3-5PbNi(CO)3. The results suggest that the molecules 1Pb, 2Pb and 4Pb possess properties which identify them as divalent Pb(0) compounds (plumbylones). This comes to the fore by the theoretically predicted second PAs which are very large for a lead compound and (for 1Pb and 4Pb) by the BDE of the second BH3 ligand. Compound 3Pb should be considered as a plumbylene-coordinated divalent C(0) compound (carbone) which has a very high second PA of 195. 1 kcal/mol. The geometry optimization of 5Pb gives an equilibrium structure which identifies the molecules as divalent Pb(II) compound, i. e., as a plumbylene.
Original language | English |
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Pages (from-to) | 615-623 |
Number of pages | 9 |
Journal | Theoretical Chemistry Accounts |
Volume | 129 |
Issue number | 3-5 |
DOIs | |
State | Published - Jun 2011 |
Externally published | Yes |
Keywords
- DFT calculations
- Divalent Pb(0) compounds
- Plumbylone
- Proton affinity
- Transition metal complexes