Combined field ion and electron microscopy and mass-spectrometry have revealed the presence of linear carbon chains at the surface of sharpened carbon fibers treated by electric fields of the order of 1011 V m−1. Linear chains attached to carbon tips consisting of more than ten atoms can be produced in situ in a field emission microscope using low-temperature pulsed-voltage field evaporation. The process of field evaporation is sporadic with an anomalously large instant rate of evaporation. Current versus voltage field electron characteristics of monoatomic carbon wires were investigated. By employing molecular dynamics simulation it was shown that atomic C-chains can be produced during the high-field unraveling of nanofibers. These chains are perfectly resolved both in electron and ion modes of the field emission microscope.

Field ion microscopic imaging of monatomic carbon chains near the ground quantum states and the visualization of their two-dimensional wave functions were demonstrated. Quantum motions with the frequency proportional to the electric field are detected and analyzed with subangstrom lateral resolution. Electric fields above 10(10) V/m can be used for control of a transverse vibration mode of atomic chains in the terahertz spectral range.

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The results of the high-field technique for obtaining and testing the carbyne strength in situ are presented. By using molecular dynamics simulation and ab initio calculations, a comprehensive analysis of the results is executed. High-field technique for experimental measurement of the carbyne strength in situ is briefly described. It is shown that the technique used gives a lower estimation for strength of carbyne, which equals 251 GPa at T = 77 K. This value is close to the strength 7.85 nN (250 GPa) of contact atomic bond between carbyne and graphene sheet, from which the monatomic chain is pulled. The strength of carbyne itself is determined by strength of an edge atomic bond and it is ≈ 12.35 nN (393 GPa) at T = 0 K. For carbynes containing more than 10 to 12 atoms, the coefficient of elasticity (kY = 145.40 nN) and the elastic modulus (Y = 4631 GPa) are ascertain.

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