resumo
Chemical bond is a ubiquitous and fundamental concept in chemistry, in which the overlap plays a defining role. By using a new approach based on localized molecular orbitals, the overlap properties, e.g., polarizability (alpha) over bar (OP), population p(OP), intra J(OP)(intra), and inter J(OP)(inter) repulsions, and density rho(OP), of polyatomic systems were calculated, analyzed, and correlated. Several trends are shown for these properties, which are rationalized by the balance of some well-known effects, such as, electron donor/withdrawing character and electronegativity. The overlap properties of unusual bonds are also analyzed, revealing an OZn4(OOCH)(6) structure with four equivalent Zn-O chemical bonds with overlap properties like the O-O bond in H2O2, while in protonated methane CH5+, it is observed that a CH3 center dot center dot center dot H-2(+) bond pattern at the equilibrium structure changes to a CH3+center dot center dot center dot H-2 pattern upon dissociation. Charge-shift resonance energies, atom-in-molecule properties, and the lone-pair-bond-weakening effects are related to the overlap properties, which can provide alternative views and insights into chemical bonds.
palavras-chave
ELECTRONIC POPULATION ANALYSIS; CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; INTENSITY PARAMETERS; WAVE FUNCTIONS; ANOMALOUS PROPERTIES; NATURAL ORBITALS; KINETIC-ENERGY; PAIR BONDS; HYDROGEN
categoria
Biochemistry & Molecular Biology; Biophysics; Chemistry; Computer Science
autores
Moura, RT; Neto, ANC; Malta, OL; Longo, RL
nossos autores
Albano Neto Carneiro Neto
Investigador Júnioragradecimentos
The authors received financial support from the Brazilian agencies CNPq, CAPES, FINEP, FACEPE, and FAPESQ/PB, under grants Pronex APQ-0859-1.06/08 and APQ-0675-1.06/14, FACEPE APQ1007-1.06/15. R.L.L. received PQ-fellowship from CNPq (Proc. no. 308823/2014-1). A.N.C.N. also thanks SusPhotoSolutions-Solucoes Fotovoltaicas Sustentaveis, CENTRO-01-0145-FEDER-000005 Sustentaveis, CENTRO-01-0145-FEDER-000005. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement.