Abstract
Structures of three tetrahalophthalic anhydrides (TXPA: halogen = Cl (TCPA), Br (TBPA), I (TIPA)) were studied by X-ray diffraction, and several types of halogen bonds (HaB) and lone pair···π-hole (lp···πh) contacts were revealed in their structures. HaBs involving the central oxygen atom of anhydride group (further X···O(anhydride) were recognized in the structures of TCPA and TBPA. In contrast, for the O(anhydride) atom of TIPA, only interactions with the π system (π-hole) of the anhydride ring (further lp(O)···πh) were observed. Computational studies by a number of theoretical methods (molecular electrostatic potentials, the quantum theory of atoms in molecules, the independent gradient model, natural bond orbital analyses, the electron density difference, and symmetry-adapted perturbation theory) demonstrated that the X···O(anhydride) contacts in TCPA and TBPA and lp(O)···πh in TIPA are caused by the packing effect. The supramolecular architecture of isostructural TCPA and TBPA was mainly affected by X···O(acyl) and X···X HaBs, and, for TIPA, the main contribution provided I···I HaBs.
Highlights
Charge transfer (CT) complexes are widely applied in different fields including sensors [1], ferroelectrics [2,3,4], ferromagnets [5], light-emitting devices [6,7], conducting materials [8,9], and catalytic systems [10]
It should be noted that the interaction of the lone pair orbitals of carboxyl oxygen and neighboring iodine atoms with a π-hole (total energy E(2) for donor-acceptor interaction lp(O) → π-hole is 0.4 kcal/mol and for lp(I) → π-hole is 0.2 kcal/mol) was observed, which stabilizes the intermolecular interaction of the two TIPA molecules
X-ray diffraction studies were performed at 100 K on an Xcalibur Eos diffractometer using Mo-Kα (λ = 0.71073 nm) radiation and SuperNova diffractometer using Cu-Kα (λ = 0.154184 nm) radiation
Summary
Charge transfer (CT) complexes are widely applied in different fields including sensors [1], ferroelectrics [2,3,4], ferromagnets [5], light-emitting devices [6,7], conducting materials [8,9], and catalytic systems [10]. Tetrahalophthalic anhydrides (TXPA) are known to form CT complexes of π···π type with a number of polycyclic aromatic compounds as electron charge acceptors [11,12,13] In this regard, crystals of TXPA, where X = Cl (TCPA), Br (TBPA), and I (TIPA) (Figure 1), have been investigated by X-ray diffraction (XRD). TXPA and and revealed revealed several several types types of of noncovalent interactions, interactions, including including early undescribed contacts, which involve central anhydride oxygen atoms (Figure early which involve involve central central anhydride anhydride oxygen oxygen atoms atoms (Figure (Figure 2) Since all these interactions can affect the properties of halogenated anhydrides, such as. Usedwide a wide range of computational methods to study these interactions between the halogenated com‐.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
