Cooperative and diminutive interplay between lithium and dihydrogen bonding in F3YLi…NCH…HMH and F3YLi…HMH…HCN triads (Y=C, Si; M=Be, Mg)

Can we quantitatively evaluate the mutual impacts of intramolecular metal-ligand bonds the same as intermolecular noncovalent bonds?

In this paper, we have reviewed several equations for calculating the cooperative energy of two chemical bonds between three fragments/species, regardless of whether they are atoms, ions or molecules, and whether the bonds between them are intra- or intermolecular. It is emphasized that two chemical bonds upon cooperation in a new compound change the bond dissociation energy of each other exactly by the same quantitative value, their cooperative energy, regardless of the nature of the bonds or whether one bond is very weak and another one is very strong. However, the final benefit/drawback of weak bonds from this cooperation can be considerably larger than that of strong bonds. The above statements are supported by a computational study on the various types of inter- and intramolecular chemical bonds.

New equation for calculating total interaction energy in one noncyclic ABC triad and new insights into cooperativity of noncovalent bonds

In this work, a new equation consist of A⋅⋅⋅B, B⋅⋅⋅C, A⋅⋅⋅BC, and AB⋅⋅⋅C interactions is proposed for calculating the total interaction energy of noncyclic ABC triads. New equations are also proposed for calculating the changes in values of A⋅⋅⋅B and B⋅⋅⋅C interactions on the formation of triad from the corresponding dyads. The advantages of equations proposed here in comparison with many-body interaction energy approach are discussed. All proposed equations were tested in F₃ MLi⋅⋅⋅NCH⋅⋅⋅HLH and F₃ MLi⋅⋅⋅HLH⋅⋅⋅HCN (M = C, Si; L = Be, Mg) as well as H₃ N⋅⋅⋅XY⋅⋅⋅HF (X, Y = F, Cl, Br) noncyclic A⋅⋅⋅B⋅⋅⋅C triads. The data show that the total cooperativity of triad correlates well with the sum of the changes in values of A⋅⋅⋅B and B⋅⋅⋅C interactions calculated through new equations proposed here. © 2016 Wiley Periodicals, Inc.

Effect of cooperativity in lithium bonding on the strength of halogen bonding and tetrel bonding: (LiCN)n···ClYF3 and (LiCN)n···YF3Cl (Y = C, Si and n = 1-5) complexes as a working model

This paper reports results of cooperativity in lithium bonding on the strength of halogen bonding and tetrel bonding in complexes pairing CF3Cl and SiF3Cl with (LiCN)n complexes, where n varies from 1 to 5. Molecular geometries and stabilization energies of title complexes are calculated at the MP2 level with 6-311++G(d,p) basis set. Cooperative effects are found in terms of structural and energetic properties when lithium, halogen, and tetrel bonds are present in these complexes simultaneously. Our results reveal that strength of halogen and tetrel bondings are enhanced due to cooperativity of Li···N interactions in lithium bonded complexes. Good linear correlations between cooperativity parameters and electronic properties of complexes were established in the present study.

Rovibrational energy and spectroscopic constant calculations of complexes pairing via dihydrogen bonds

In the present investigation, we performed a thorough study of potential energy curves, rovibrational spectra, and spectroscopic constants for complexes pairing via dihydrogen bonds. In particular, we dealt with LiH···HX (X = F, CN, CCH, CCF, CCCl) complexes by employing accurate electronic energy calculations at the MP2/aug-cc-pVDZ level of theory. Following this, the Numerov method was applied to solve the nuclear Schrödinger equation, thus obtaining spectroscopic constants and rovibrational spectra. Good linear correlation between the magnitudes of the interaction energies for interaction of HX with LiH, and the most positive electrostatic potentials of hydrogen in HX, was established.