Halogen bonding in polymer science: towards new smart materials

Abstract

The incorporation of halogen bonding into polymer architectures is a new approach for the design of functional materials. This perspective emphasizes the current development in the field of halogen bonding featuring polymer materials.

On the Importance of σ–Hole Interactions in Crystal Structures

“…The halogen bonding interaction is likely the most studied and reviewed noncovalent interaction after the ubiquitous hydrogen bonding [29][30][31][32][33][34][35][36][37][38][39]. Remarkably, the seminal HaB has inspired the scientific community to further investigate and rationalize the ability of the other elements of the p-block to form analogous ChB, PnB, TtBs, and NgBs and to expand the σ-hole concept.…”

“…Remarkably, the seminal HaB has inspired the scientific community to further investigate and rationalize the ability of the other elements of the p-block to form analogous ChB, PnB, TtBs, and NgBs and to expand the σ-hole concept. Since there is a considerable amount of information available for the readers in the form of reviews and book chapters devoted to HaB [29][30][31][32][33][34][35][36][37][38][39], this interaction is briefly described in this section of the present review.…”

“…HaBs involving bromine and iodine as σ-hole donors have been used in a wide variety of fields, including crystal engineering, catalysis, supramolecular chemistry, molecular recognition of anions, and membrane transport [28][29][30][31][32][33][34][35][36][37][38][39][47][48][49][50][51]. Therefore, this section is devoted to discussing more unconventional and recent investigations on halogen bonding in which the Lewis base is a transition metal complex.…”

“…In this regard, several studies have demonstrated that σ-holes (regions of positive electrostatic potential located on the extension of covalent bonds) can be used in a broad spectrum of fields, such as host-guest chemistry, catalysis, supramolecular chemistry, membrane transport, crystal engineering, etc. Noteworthy review articles, accounts, and book chapters are available in the literature describing promising applications and basic features of the σ-hole group of NCIs [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45]. Moreover, several works have been devoted to the comparison of the geometric and energetic characteristics of σ-hole interactions to the HB [46][47][48][49][50][51].…”

Exploring Orthogonality between Halogen and Hydrogen Bonding Involving Benzene

“…Halogen bonding (XB), a noncovalent interaction where the halogen atom acts as electrophilic species [ 1 ], is nowadays a well-recognized molecular interaction with applications in biochemistry [ 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ] and materials science [ 12 , 13 ], including non-linear optics [ 14 , 15 , 16 ] and liquid crystals [ 17 , 18 , 19 ]. This interaction, schematized as R–X···B (X = Cl, Br, or I; B = Lewis base; R = substituent), has been explained by the existence of a region of positive electrostatic potential, named σ-hole, on the outermost surface of the covalently-bonded halogen atom and narrowly confined on the elongation of the R–X covalent bond axis [ 20 ].…”