Observation of a two-dimensional halogen-bonded cocrystal at sub-monolayer coverage using synchrotron X-ray diffraction

Clarke, Stuart M.; Friščić, Tomislav; Jones, William; Mandal, Anasuya; Sun, Chengguo; Parker, Julia

doi:10.1039/c0cc04400h

Cited by 34 publications

(36 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the BPY/DITFB colayer structure (see figure 2b in ref (10)), the molecules form extended chains of alternating DITFB and BPY. There is evidence of a strong halogen bond between the iodine atoms of DITFB and the nitrogen atoms of BPY, as deduced from the internuclear separation (2.84 Å), which is shorter than the sum of the van der Waals radii of the species.…”

Section: Introductionmentioning

confidence: 99%

Combined Diffraction and Density Functional Theory Calculations of Halogen-Bonded Cocrystal Monolayers

Sacchi¹,

Brewer²,

Jenkins³

et al. 2013

Langmuir

Self Cite

View full text Add to dashboard Cite

This work describes the combined use of synchrotron X-ray diffraction and density functional theory (DFT) calculations to understand the cocrystal formation or phase separation in 2D monolayers capable of halogen bonding. The solid monolayer structure of 1,4-diiodobenzene (DIB) has been determined by X-ray synchrotron diffraction. The mixing behavior of DIB with 4,4′-bipyridyl (BPY) has also been studied and interestingly is found to phase-separate rather than form a cocrystal, as observed in the bulk. DFT calculations are used to establish the underlying origin of this interesting behavior. The DFT calculations are demonstrated to agree well with the recently proposed monolayer structure for the cocrystal of BPY and 1,4-diiodotetrafluorobenzene (DITFB) (the perfluorinated analogue of DIB), where halogen bonding has also been identified by diffraction. Here we have calculated an estimate of the halogen bond strength by DFT calculations for the DITFB/BPY cocrystal monolayer, which is found to be ∼20 kJ/mol. Computationally, we find that the nonfluorinated DIB and BPY are not expected to form a halogen-bonded cocrystal in a 2D layer; for this pair of species, phase separation of the components is calculated to be lower energy, in good agreement with the diffraction results.

show abstract

Section: Introductionmentioning

confidence: 99%

Combined Diffraction and Density Functional Theory Calculations of Halogen-Bonded Cocrystal Monolayers

Sacchi¹,

Brewer²,

Jenkins³

et al. 2013

Langmuir

Self Cite

View full text Add to dashboard Cite

show abstract

“…This contrasts with many sub-monolayer coverage physisorbed layers, which show melting points lowered by a greater degree relative to the bulk, typically by a factor of approximately 0.75. While some molecules do form solid monolayers close to, or indeed on rare occasions above [5,7,12], the bulk melting point even at sub-monolayer coverages, such layers are normally stabilized by strong intermolecular interactions like hydrogen bonds [5,12].…”

Section: Discussionmentioning

confidence: 99%

“…Molecules containing pyridine moieties are notable for their ability to act as ligands, allowing surface selfassembly via a range of non-covalent interactions such as hydrogen bonding [3,4], halogen bonding [5] and metal coordination [2]. In addition, these molecules have been shown to form ordered single-component monolayers, whose structure is guided by the formation of weak C-H � � � N hydrogen bonds [6,7].…”

Section: Introductionmentioning

confidence: 98%

The monolayer structure of 1,2-bis(4-pyridyl)ethylene physisorbed on a graphite surface

Brewer¹,

Friščić²,

Day³

et al. 2012

Molecular Physics

Self Cite

View full text Add to dashboard Cite

The crystalline monolayer of 1,2-bis(4-pyridyl)ethylene physisorbed on a graphite surface at 0.44 monolayers coverage has been observed and characterized by synchrotron X-ray diffraction and differential scanning calorimetry. The experimentally determined monolayer structure has p2 symmetry with lattice parameters a ¼ 17.77 Å , b ¼ 13.69 Å and ¼ 39.7 � . The unit cell contains two molecules, which are oriented in a plane parallel to the surface. It is proposed that the molecules are arranged such that they are able to form a weak C-H � � � N hydrogen bond between pyridine groups. The monolayer melts at 414 K, which is unusually close to the bulk melting point for a sub-monolayer coverage system. This molecule is chiral when adsorbed on the surface, but both isomers appear in the unit cell leading to no overall chirality in the monolayer.

show abstract

“…The apparatus and procedures for the synchrotron X-ray [24,28], Neutron [9,36] and DSC [19,37] have been described elsewhere. The instrument used for the synchrotron experiment was I11 [38] at the Diamond Light Source, Didcot, UK.…”

Section: Methodsmentioning

confidence: 99%

“…In addition alkyl species with functional groups such as alcohols [15][16][17][18][19][20] and fatty acids [21][22][23] are also reported to form similar stable solid monolayers. Recently it has been found that the formation of very stable solid monolayers can be enhanced by a variety of non-covalent interactions within the monolayer, such as hydrogen bonding [24][25][26][27], halogen-halogen bonding [28,29], halogen bonding [28] even at temperatures significantly above the bulk melting point where the bulk adsorbate is liquid.…”

Section: Introductionmentioning

confidence: 99%

The structures of 1-bromoheptane and 1-bromononane monolayers adsorbed on the surface of graphite

Sun¹,

Clarke²,

Brewer³

et al. 2012

Molecular Physics

View full text Add to dashboard Cite

X-ray diffraction and differential scanning calorimetry (DSC) have been used to confirm the formation of the solid monolayers of 1-bromoheptane (C7Br) and 1-bromononane (C9Br) on the surface of graphite. The X-ray diffraction patterns of these two species can be fitted by two possible monolayer structures with symmetries Pgb and P2. For one of these (C7Br) this ambiguity can be lifted using neutron diffraction and the Pgb plane group can be identified as the correct structural solution. Both of the unit cells contain two molecules forming an approximately 90 o zig-zag chain of bromine atoms with an inter-bromine distance of approximately 3.70 Å , which is similar to twice the Van der Waals radii of the bromine, suggesting rather little non-covalent interaction. The dipole moments in two adjacent chains are opposed leading to no net dipole for the layer as a whole.

show abstract

Observation of a two-dimensional halogen-bonded cocrystal at sub-monolayer coverage using synchrotron X-ray diffraction

Cited by 34 publications

References 33 publications

Combined Diffraction and Density Functional Theory Calculations of Halogen-Bonded Cocrystal Monolayers

Combined Diffraction and Density Functional Theory Calculations of Halogen-Bonded Cocrystal Monolayers

The monolayer structure of 1,2-bis(4-pyridyl)ethylene physisorbed on a graphite surface

The structures of 1-bromoheptane and 1-bromononane monolayers adsorbed on the surface of graphite

Contact Info

Product

Resources

About