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The nature of hydrogen-bonding interaction in the prototypic hybrid halide perovskite, tetragonal CH3NH3PbI3.

Lee JH, Lee JH, Kong EH, Jang HM - Sci Rep (2016)

Bottom Line: Herein, we show that there exist two distinct types of the hydrogen-bonding interaction, naming α- and β-modes, in the tetragonal MAPbI3 on the basis of symmetry argument and density-functional theory calculations.The computed Kohn-Sham (K-S) energy difference between these two interaction modes is 45.14 meV per MA-site with the α-interaction mode being responsible for the stable hydrogen-bonding network.The computed bandgap (Eg) is also affected by the hydrogen-bonding mode, with Eg of the α-interaction mode (1.73 eV) being significantly narrower than that of the β-interaction mode (2.03 eV).

View Article: PubMed Central - PubMed

Affiliation: Department of Materials Science and Engineering, and Division of Advanced Materials Science (AMS), Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea.

ABSTRACT
In spite of the key role of hydrogen bonding in the structural stabilization of the prototypic hybrid halide perovskite, CH3NH3PbI3 (MAPbI3), little progress has been made in our in-depth understanding of the hydrogen-bonding interaction between the MA(+)-ion and the iodide ions in the PbI6-octahedron network. Herein, we show that there exist two distinct types of the hydrogen-bonding interaction, naming α- and β-modes, in the tetragonal MAPbI3 on the basis of symmetry argument and density-functional theory calculations. The computed Kohn-Sham (K-S) energy difference between these two interaction modes is 45.14 meV per MA-site with the α-interaction mode being responsible for the stable hydrogen-bonding network. The computed bandgap (Eg) is also affected by the hydrogen-bonding mode, with Eg of the α-interaction mode (1.73 eV) being significantly narrower than that of the β-interaction mode (2.03 eV). We have further estimated the individual bonding strength for the ten relevant hydrogen bonds having a bond critical point.

No MeSH data available.


Graphical illustration of the two distinct sets of the MA+-ion orientations (at a given MA-site) in the tetragonal MAPbI3 with D2d symmetry.(upper panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {+A, −B, +C, −D}. (lower panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {−A, +B, −C, +D}.
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f2: Graphical illustration of the two distinct sets of the MA+-ion orientations (at a given MA-site) in the tetragonal MAPbI3 with D2d symmetry.(upper panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {+A, −B, +C, −D}. (lower panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {−A, +B, −C, +D}.

Mentions: In the room-temperature-stable tetragonal phase, on the contrary, the PbI6 octahedral network belongs to D2d point group owing to the tilt pattern. Thus, the PbI6-cage network is characterized by the S4 improper rotation axis along the c-axis (Fig. 1c). Because of the S4 improper rotation, a set of the following four distinct orientations of the C-N bond axis (at a given arbitrary MA-site) is under the same chemical environment: {+A, −B, +C, −D}. Similarly, a set of the orientations, {−A, +B, −C, +D}, at a given MA-site is chemically equivalent in the tetragonal phase. Consequently, there exist two distinct chemical environments (also, energetically non-degenerate) for the MA+-ion orientation in the tetragonal phase. These two distinct sets of orientations are graphically illustrated in Fig. 2: {+A, −B, +C, −D} in the upper panel and {−A, +B, −C, +D} in the lower panel.


The nature of hydrogen-bonding interaction in the prototypic hybrid halide perovskite, tetragonal CH3NH3PbI3.

Lee JH, Lee JH, Kong EH, Jang HM - Sci Rep (2016)

Graphical illustration of the two distinct sets of the MA+-ion orientations (at a given MA-site) in the tetragonal MAPbI3 with D2d symmetry.(upper panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {+A, −B, +C, −D}. (lower panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {−A, +B, −C, +D}.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4759593&req=5

f2: Graphical illustration of the two distinct sets of the MA+-ion orientations (at a given MA-site) in the tetragonal MAPbI3 with D2d symmetry.(upper panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {+A, −B, +C, −D}. (lower panel) The central MA+-ion viewed along [110] (upper row) and viewed along [001] (lower row) for a set of the four distinct orientations, {−A, +B, −C, +D}.
Mentions: In the room-temperature-stable tetragonal phase, on the contrary, the PbI6 octahedral network belongs to D2d point group owing to the tilt pattern. Thus, the PbI6-cage network is characterized by the S4 improper rotation axis along the c-axis (Fig. 1c). Because of the S4 improper rotation, a set of the following four distinct orientations of the C-N bond axis (at a given arbitrary MA-site) is under the same chemical environment: {+A, −B, +C, −D}. Similarly, a set of the orientations, {−A, +B, −C, +D}, at a given MA-site is chemically equivalent in the tetragonal phase. Consequently, there exist two distinct chemical environments (also, energetically non-degenerate) for the MA+-ion orientation in the tetragonal phase. These two distinct sets of orientations are graphically illustrated in Fig. 2: {+A, −B, +C, −D} in the upper panel and {−A, +B, −C, +D} in the lower panel.

Bottom Line: Herein, we show that there exist two distinct types of the hydrogen-bonding interaction, naming α- and β-modes, in the tetragonal MAPbI3 on the basis of symmetry argument and density-functional theory calculations.The computed Kohn-Sham (K-S) energy difference between these two interaction modes is 45.14 meV per MA-site with the α-interaction mode being responsible for the stable hydrogen-bonding network.The computed bandgap (Eg) is also affected by the hydrogen-bonding mode, with Eg of the α-interaction mode (1.73 eV) being significantly narrower than that of the β-interaction mode (2.03 eV).

View Article: PubMed Central - PubMed

Affiliation: Department of Materials Science and Engineering, and Division of Advanced Materials Science (AMS), Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea.

ABSTRACT
In spite of the key role of hydrogen bonding in the structural stabilization of the prototypic hybrid halide perovskite, CH3NH3PbI3 (MAPbI3), little progress has been made in our in-depth understanding of the hydrogen-bonding interaction between the MA(+)-ion and the iodide ions in the PbI6-octahedron network. Herein, we show that there exist two distinct types of the hydrogen-bonding interaction, naming α- and β-modes, in the tetragonal MAPbI3 on the basis of symmetry argument and density-functional theory calculations. The computed Kohn-Sham (K-S) energy difference between these two interaction modes is 45.14 meV per MA-site with the α-interaction mode being responsible for the stable hydrogen-bonding network. The computed bandgap (Eg) is also affected by the hydrogen-bonding mode, with Eg of the α-interaction mode (1.73 eV) being significantly narrower than that of the β-interaction mode (2.03 eV). We have further estimated the individual bonding strength for the ten relevant hydrogen bonds having a bond critical point.

No MeSH data available.