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Three-Dimensional Carbon Allotropes Comprising Phenyl Rings and Acetylenic Chains in sp+sp(2) Hybrid Networks.

Wang JT, Chen C, Li HD, Mizuseki H, Kawazoe Y - Sci Rep (2016)

Bottom Line: These structures are constructed by inserting acetylenic or diacetylenic bonds into an all sp(2)-hybridized rhombohedral polybenzene lattice, and the resulting 3D phenylacetylene and phenyldiacetylene nets comprise a 12-atom and 18-atom rhombohedral primitive unit cells in the symmetry, which are characterized as the 3D chiral crystalline modification of 2D graphyne and graphdiyne, respectively.Simulated phonon spectra reveal that these structures are dynamically stable.The present results establish a new type of carbon phases and offer insights into their outstanding structural and electronic properties.

View Article: PubMed Central - PubMed

Affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.

ABSTRACT
We here identify by ab initio calculations a new type of three-dimensional (3D) carbon allotropes that consist of phenyl rings connected by linear acetylenic chains in sp+sp(2) bonding networks. These structures are constructed by inserting acetylenic or diacetylenic bonds into an all sp(2)-hybridized rhombohedral polybenzene lattice, and the resulting 3D phenylacetylene and phenyldiacetylene nets comprise a 12-atom and 18-atom rhombohedral primitive unit cells in the symmetry, which are characterized as the 3D chiral crystalline modification of 2D graphyne and graphdiyne, respectively. Simulated phonon spectra reveal that these structures are dynamically stable. Electronic band calculations indicate that phenylacetylene is metallic, while phenyldiacetylene is a semiconductor with an indirect band gap of 0.58 eV. The present results establish a new type of carbon phases and offer insights into their outstanding structural and electronic properties.

No MeSH data available.


Phonon band structures and partial density of states (DOS).Results for rh12 phenylacetylene (a) and rh18 phenyldiacetylene (b). The spectra due to the triple bonds and phenyl bonds occur around 2150 cm−1 and 1500 cm−1, respectively. A clearer picture for the low vibrational modes is given in Fig. S1 in Supplementary Information.
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f3: Phonon band structures and partial density of states (DOS).Results for rh12 phenylacetylene (a) and rh18 phenyldiacetylene (b). The spectra due to the triple bonds and phenyl bonds occur around 2150 cm−1 and 1500 cm−1, respectively. A clearer picture for the low vibrational modes is given in Fig. S1 in Supplementary Information.

Mentions: We next examine the dynamic stability of the 3D sp+sp2 bonding networks by phonon mode analysis. Figure 3a shows the phonon band structures and density of state (DOS) for the 3D phenylacetylene. The obtained phonon eigenvalues can be explained well by considering the bonding nature of the phenyl and triple carbon-carbon bonds. The vibrational modes due to the triple yne-bond can be observed clearly around 2150 cm−1 with the carbon-carbon bond length of 1.232 Å (C2–C2) and the vibrational modes due to the phenyl bonds are distributed around 1500 cm−1 with the carbon-carbon bond length of 1.433 Å (C1–C1). The combination modes of phenyl and triple bonds of carbon atoms can be seen clearly below 730 cm−1. No imaginary frequencies were observed throughout the entire phonon band structures, thus confirming the dynamic stability of the 3D-phenylacetylene. Meanwhile, there is a large phonon band gap in the frequency range of 1500 and 2100 cm−1. Similar dynamic stability and vibrational modes are also confirmed for 3D phenyldiacetylene as shown in Fig. 3b. However, in the latter case there are two yne-modes around 2148 and 2193 cm−1 due to the diyne bonds related to the C2 and C3 carbon atoms.


Three-Dimensional Carbon Allotropes Comprising Phenyl Rings and Acetylenic Chains in sp+sp(2) Hybrid Networks.

Wang JT, Chen C, Li HD, Mizuseki H, Kawazoe Y - Sci Rep (2016)

Phonon band structures and partial density of states (DOS).Results for rh12 phenylacetylene (a) and rh18 phenyldiacetylene (b). The spectra due to the triple bonds and phenyl bonds occur around 2150 cm−1 and 1500 cm−1, respectively. A clearer picture for the low vibrational modes is given in Fig. S1 in Supplementary Information.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4834540&req=5

f3: Phonon band structures and partial density of states (DOS).Results for rh12 phenylacetylene (a) and rh18 phenyldiacetylene (b). The spectra due to the triple bonds and phenyl bonds occur around 2150 cm−1 and 1500 cm−1, respectively. A clearer picture for the low vibrational modes is given in Fig. S1 in Supplementary Information.
Mentions: We next examine the dynamic stability of the 3D sp+sp2 bonding networks by phonon mode analysis. Figure 3a shows the phonon band structures and density of state (DOS) for the 3D phenylacetylene. The obtained phonon eigenvalues can be explained well by considering the bonding nature of the phenyl and triple carbon-carbon bonds. The vibrational modes due to the triple yne-bond can be observed clearly around 2150 cm−1 with the carbon-carbon bond length of 1.232 Å (C2–C2) and the vibrational modes due to the phenyl bonds are distributed around 1500 cm−1 with the carbon-carbon bond length of 1.433 Å (C1–C1). The combination modes of phenyl and triple bonds of carbon atoms can be seen clearly below 730 cm−1. No imaginary frequencies were observed throughout the entire phonon band structures, thus confirming the dynamic stability of the 3D-phenylacetylene. Meanwhile, there is a large phonon band gap in the frequency range of 1500 and 2100 cm−1. Similar dynamic stability and vibrational modes are also confirmed for 3D phenyldiacetylene as shown in Fig. 3b. However, in the latter case there are two yne-modes around 2148 and 2193 cm−1 due to the diyne bonds related to the C2 and C3 carbon atoms.

Bottom Line: These structures are constructed by inserting acetylenic or diacetylenic bonds into an all sp(2)-hybridized rhombohedral polybenzene lattice, and the resulting 3D phenylacetylene and phenyldiacetylene nets comprise a 12-atom and 18-atom rhombohedral primitive unit cells in the symmetry, which are characterized as the 3D chiral crystalline modification of 2D graphyne and graphdiyne, respectively.Simulated phonon spectra reveal that these structures are dynamically stable.The present results establish a new type of carbon phases and offer insights into their outstanding structural and electronic properties.

View Article: PubMed Central - PubMed

Affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.

ABSTRACT
We here identify by ab initio calculations a new type of three-dimensional (3D) carbon allotropes that consist of phenyl rings connected by linear acetylenic chains in sp+sp(2) bonding networks. These structures are constructed by inserting acetylenic or diacetylenic bonds into an all sp(2)-hybridized rhombohedral polybenzene lattice, and the resulting 3D phenylacetylene and phenyldiacetylene nets comprise a 12-atom and 18-atom rhombohedral primitive unit cells in the symmetry, which are characterized as the 3D chiral crystalline modification of 2D graphyne and graphdiyne, respectively. Simulated phonon spectra reveal that these structures are dynamically stable. Electronic band calculations indicate that phenylacetylene is metallic, while phenyldiacetylene is a semiconductor with an indirect band gap of 0.58 eV. The present results establish a new type of carbon phases and offer insights into their outstanding structural and electronic properties.

No MeSH data available.