FRONTIER MOLECULAR ORBITALS OF COMMON LIGANDS INTERACTING THROUGH FOUR CARBON ATOMS

All web pages were generated using WEBMO and the calculations were carried out using GAUSSIAN suite of programs.

This page connects you to the pages with frontier molecular orbitals of small molecules and ligands which interact with transition metals through four carbon atoms like butadiene

   
4_CARBON_LIGANDS MOLECULE GEOMETRY MOLECULAR ORBITALS VIBRATIONS BOND ORDER






Cisoid form of C4H6
 BUTADIENE
BUTADIENE







Triplet state! Square CBD
 CYCLOBUTADIENE
CYCLOBUTADIENE

 [C4H4}2- Singlet*
 [Cyclobutadiene] 2-
[Cyclobutadiene] 2-


Bis Acetylene Suitable for CpCo Bis acetylene group


 Bis Ethylene Suitable for CpCo Bis Ethylene group


tetrakis Carbonyl
 Suitable for CpV
 Tetrakis CO group

Trimethylenemethane* [TMM]
 [TMM]2-
 [TMM]2-


3[TMM] 3[TMM] 3[TMM]


Complexed TMM

[TMM]2- as in [Fe(CO)3 ] complex


*  The stable form of the free molecule is a triplet. To make it a singlet, we make it a dianion by adding 2 electrons as deciphering triplet MO's are difficult.

To understand how the MO's would look like one should consider that the HOMO is singly occupied and not doubly as shown in this picture.

The energy levels and the geometry of the molecule are however affected by the charge. .As a result the MO's of TMM as found in the complex have been generated for matching with Fe(CO)3 in TMM(Complex)