Group 12 Carbonates and their Binary Complexes with Nitrogen Bases and FH₂Z Molecules (Z=P, As, Sb): Synergism in Forming Ternary Complexes

Abstract

MCO 3 (M=Zn, Cd, Hg) forms a spodium bond with nitrogencontaining bases (HCN, NHCH 2 , NH 3 ) and a pnicogen bond with FH 2 Z (Z=P, As, Sb). The spodium bond is very strong with the interaction energy ranging from À 31 kcal/mol to À 56 kcal/mol. Both NHCH 2 and NH 3 have an equal electrostatic potential on the N atom, but the corresponding interaction energy is differentiated by 1.5-4 kcal/mol due to the existence of spodium and hydrogen bonds in the complex with NHCH 2 as the electron donor. The spodium bond is weakest in the HCN complex, which is not consistent with the change of the binding distance. The spodium bond becomes stronger in the CdCO 3 < ZnCO 3 < HgCO 3 sequence although the positive electrostatic potential on the Hg atom is smallest. This is because the electrostatic interaction is dominant in the spodium-bonded complexes of CdCO 3 and ZnCO 3 but the polarization interaction in that of HgCO 3 . The pnicogen bond is much weaker than the spodium bond and the former has a larger enhancement than the latter in the FH 2 Z•••OCO 2 M•••N-base ternary complexes.

Single‐electron spodium bonds: Substituent effects

“…[4][5][6] Consequently, some interests have been focused on the structures, properties, nature, and applications of spodium bonds. [7][8][9][10][11][12][13][14][15][16][17][18][19] Joy and Jemmis [20] have pointed out that metals in Group 12 of the periodic table, acting as Lewis acids, may be involved in noncovalent interactions (NCIs) before the concept of spodium bond was raised. The first evidence for this type of bond was reported for the structure of dichloro-bis(thiosemicarbazide)-mercury(II) in 1977.…”

“…[7] The relatively big polarization energy stands for that the spodium bond has some amount of covalency; therefore, it is of interest to distinguish between the noncovalent spodium bond and the corresponding covalent bond. [10,11] In constructing supramolecular aggregates with spodium bonding, it is often found that this type of bonding coexists with other varieties of NCIs [12] ; for instance, Liu and coauthors [13][14][15][16] investigated the interplay between the spodium bond and other NCIs including hydrogen, halogen, pnicogen, chalcogen, and tetrel bonds. Similar to other NCIs, the electron donors in the spodium bond can also be quite diverse, ranging from molecules containing lone pairs and anions to π-electron molecules [17,18] and carbenes.…”

“…[ 4–6 ] Consequently, some interests have been focused on the structures, properties, nature, and applications of spodium bonds. [ 7–19 ]…”

“…In constructing supramolecular aggregates with spodium bonding, it is often found that this type of bonding coexists with other varieties of NCIs [ 12 ] ; for instance, Liu and coauthors [ 13–16 ] investigated the interplay between the spodium bond and other NCIs including hydrogen, halogen, pnicogen, chalcogen, and tetrel bonds. Similar to other NCIs, the electron donors in the spodium bond can also be quite diverse, ranging from molecules containing lone pairs and anions to π‐electron molecules [ 17,18 ] and carbenes.…”

Properties and Stabilities of Cyclic and Open Chains of Halogen Bonds

“…The latter are characterized by the replacement of the bridging proton by any of a wide assortment of other atoms, most more electronegative than H. These interactions are commonly categorized in reference to the family of elements from which this replacement bridging atom is drawn. The chalcogen bond, − for example, makes use of S, Se, and Te, while the involvement of P, As, or Sb leads to the designation as a pnicogen bond. − …”