Comparison of linear-scaling semiempirical methods and combined quantum mechanical/molecular mechanical methods for enzymic reactions. II. An energy decomposition analysis

Ferrocenium (Fc+) inherits a number of molecular/electronic properties from the neutral counterparts’ ferrocene (Fc) including the high symmetry. Both Fc+ and Fc prefer the eclipsed structure (D5h) over the staggered structure (D5d) by an energy of 0.36 kcal·mol-1. The present study using the recently developed excess orbital energy spectrum (EOES) shows that the open shell Fc+ cation exhibits similar conformer dependent configurational changes to the neutral Fc conformer pair. A further energy decomposition analysis (EDA) discloses that the reasons for the preferred structures are different between Fc+ and Fc. The dominant differentiating energy between the Fc+ conformers is the electrostatic energy (EEstat), whereas in neutral Fc, it is the quantum mechanical Pauli repulsive energy (EPauli). Within the D5h conformer of Fc+, the EOES reveals that the -electrons of Fc+ experience more substantial conformer dependent energy changes than the -electrons (assumed the hole is in a β orbital).

Download Full-text

VERY DIFFERENT CH3 INTERNAL ROTATION BARRIERS IN THE SYN- AND ANTI- FORMS OF THIOACETIC ACID: MICROWAVE MEASUREMENTS AND ENERGY DECOMPOSITION ANALYSIS

Proceedings of the 73rd International Symposium on Molecular Spectroscopy ◽

10.15278/isms.2018.wh07 ◽

2018 ◽

Author(s):

CJ Smith ◽

Yirong Mo ◽

Huaiyu Zhang ◽

Ken Leopold ◽

Anna Huff

Keyword(s):

Internal Rotation ◽

Decomposition Analysis ◽

Energy Decomposition Analysis ◽

Microwave Measurements ◽

Thioacetic Acid ◽

Energy Decomposition

Download Full-text

Energy Decomposition Analysis Reveals the Nature of Lone Pair−π Interactions with Cationic π Systems in Catalytic Acyl Transfer Reactions

Organic Letters ◽

10.1021/acs.orglett.1c01351 ◽

2021 ◽

Author(s):

Hua Hao ◽

Xiaotian Qi ◽

Weiping Tang ◽

Peng Liu

Keyword(s):

Decomposition Analysis ◽

Lone Pair ◽

Acyl Transfer ◽

Transfer Reactions ◽

Energy Decomposition Analysis ◽

Energy Decomposition ◽

Π Interactions ◽

Acyl Transfer Reactions

Download Full-text

Direct estimate of the internal π-donation to the carbene centre within N-heterocyclic carbenes and related molecules

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.11.294 ◽

2015 ◽

Vol 11 ◽

pp. 2727-2736 ◽

Cited By ~ 38

Author(s):

Diego M Andrada ◽

Nicole Holzmann ◽

Thomas Hamadi ◽

Gernot Frenking

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Decomposition Analysis ◽

Heterocyclic Carbenes ◽

Energy Decomposition Analysis ◽

Energy Decomposition ◽

Direct Estimate ◽

Functional Theory ◽

Bonding Analysis

Fifteen cyclic and acylic carbenes have been calculated with density functional theory at the BP86/def2-TZVPP level. The strength of the internal X→p(π) π-donation of heteroatoms and carbon which are bonded to the C(II) atom is estimated with the help of NBO calculations and with an energy decomposition analysis. The investigated molecules include N-heterocyclic carbenes (NHCs), the cyclic alkyl(amino)carbene (cAAC), mesoionic carbenes and ylide-stabilized carbenes. The bonding analysis suggests that the carbene centre in cAAC and in diamidocarbene have the weakest X→p(π) π-donation while mesoionic carbenes possess the strongest π-donation.

Download Full-text