How strong are the metallocene–metallocene interactions? Cases of ferrocene, ruthenocene, and osmocene

Abstract

An exhaustive exploration of the potential energy surfaces of ferrocene, ruthenocene and osmocene dimers has been performed. Our computations involving dispersion show that only four different isomers are present in each metallocene dimer. The collective action of small interaction energies of dispersive nature leads to a dissociation energy of 7.5 kcal mol(-1) for the ferrocene dimer. Dispersion has strong effects on the geometrical parameters, reducing the M···M distances by almost 1 Å. Our results also reveal that inclusion of entropic factors modifies the relative stability of the complexes. The nature of bonding is examined using the energy decomposition analysis and the non-covalent interaction index. Both analyses indicate that dispersion is the major contributing factor in stabilizing a metallocene dimer.

Theoretical Prediction of Structures, Vibrational Circular Dichroism, and Infrared Spectra of Chiral Be4B8 Cluster at Different Temperatures

“…Several algorithms to explore the potential/free energy surface coupled to an any electronic structure package have been successfully employed so far, such as AIRSS approach, [ 98 ] simulated annealing, [ 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 , 104 ], kick methodology [ 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 ], and genetic algorithms [ 9 , 21 , 33 , 112 , 116 , 117 , 118 , 119 ], among others.…”

Theory and practice of modeling van der Waals interactions in electronic-structure calculations

“…Hence, the NCI approach often does not necessarily require a full DFT calculation 78 and has been successfully applied also to large-scale systems including porous crystalline materials, metal and guest-host complexes, OH-p interactions, and proteins. [78][79][80][81][82][83] Especially regarding repulsive interactions, we would like to point out that care must be taken when using a non-self-consistent density. In a promolecular density there is no Pauli-repulsion between the atomic densities to cause charge depletion.…”

Stacking Interactions between Indenyl Ligands of Transition Metal Complexes: Crystallographic and Density Functional Study

“…Moreover, since previous work of Merino et al showed that stacking energies of Cp sandwich complexes of 3d, 4d and 5d metals are significantly different, 55 we have modified the metals in selected complexes by always using the metals of the same transition row. We have chosen 4d metals, since majority of indenyl complexes forming stacking interactions are with 4d metals (see Figure S2, Supporting Information).…”