Electronic structure of carbynes studied by Auger and electron energy loss spectroscopy

Carbyne with finite length: The one-dimensional sp carbon

“…Astrophysicists have proposed that, based on the observation of a new hexagonal carbon phase in meteorites, carbyne might exist as meteorites ( 9 ) and as a by-product of shock-fused graphite ( 10 ). Materials physicists have reported the presence of similar hexagonal carbon phases in the laboratory syntheses of carbyne by a number of routes, such as graphite sublimation and dehydrohalogenation of polymers ( 11 , 12 ). In these cases, there was no substantial evidence of the existence of carbyne (that is, a linear one-dimensional framework composed of sp -hybridized carbon atoms) in the resulting products.…”

“…The corresponding selected area electron diffraction (SAED) patterns and high-resolution TEM (HRTEM) images of the carbyne crystals were obtained. We studied more than 30 carbyne crystals and divided their SAED patterns and HRTEM images into three categories based on the direction of the incident electron beam (that is, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], [012], and [001]), as shown in Fig. 4 (D to I).…”

Linear carbon allotrope – carbon atom wires prepared by pyrolysis of starch

“…4a, the peak of 4.6 eV and the should of 3.4 eV that are characteristic of the strong p-p à interband transition and p-interband plasmon, and the peak of 23.6 eV and the shoulder of 20.2 eV that arise from plasma resonance of all valence electrons (p þ r plasmon) can be found and are shifted to the lower energy values than the corresponding values of graphite, as the case of carbynes and carbynoid samples [17,20]. EELS spectrum of carbon K-edge shown in Fig.…”

“…EELS spectrum of carbon K-edge shown in Fig. 4b is also characteristic of carbyne rather than graphite or diamond [17,20].…”

Ageing of chemically modified poly(vinylidene fluoride) film: Evolution of triple carbon-carbon bonds infrared absorption

“…Chains should be packed in crystals due to van der Waals forces. The band gap for infinite carbyne in vacuum is calculated, and a wide variety of values ranging from 0.2 to 8.5 eV have been reported [11], but the most of experimental studies reveal that carbyne-like structures have semiconducting properties [1,12,13]. There are different and often contradictory structural models of carbyne chains and their mutual ordering [1,2,4].…”