Research output: Contribution to journal › Article › peer-review
Formation of Compressed and Mixed-Layered Graphite on Heating Impact Diamonds. / Gromilov, S. A.; Nikolaev, R. E.; Cherepanova, S. V.
In: Journal of Structural Chemistry, Vol. 59, No. 2, 01.03.2018, p. 355-364.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Formation of Compressed and Mixed-Layered Graphite on Heating Impact Diamonds
AU - Gromilov, S. A.
AU - Nikolaev, R. E.
AU - Cherepanova, S. V.
PY - 2018/3/1
Y1 - 2018/3/1
N2 - The graphitization process of impact diamonds in the helium atmosphere at 1900–1960 °C is investigated. It is shown that when an impact diamond particle with a large number of lonsdaleite defects is kept at 1900 °C for 1 min, ~5 wt.% of graphite are formed (in the paralle experiment with a particle without lonsdaleite defects the graphite formation is not observed). With an increase in the temperature to 1930 °С and 1940 °С the graphite amount increases to 70 wt.% and 80 wt.% respectively. In both cases, a mixture of two graphite phases forms: the first is turbostratic graphite with d002 = 3.38 Å; the second is compressed graphite with d002 = 3.21 Å. On heating a particle to 1960 °C graphite is formed in which the layer packing contains a large amount of defects and is a mixture of 2Н and 3R polytypes (the ratio 40:60) with a small degree of turbostratic disordering.
AB - The graphitization process of impact diamonds in the helium atmosphere at 1900–1960 °C is investigated. It is shown that when an impact diamond particle with a large number of lonsdaleite defects is kept at 1900 °C for 1 min, ~5 wt.% of graphite are formed (in the paralle experiment with a particle without lonsdaleite defects the graphite formation is not observed). With an increase in the temperature to 1930 °С and 1940 °С the graphite amount increases to 70 wt.% and 80 wt.% respectively. In both cases, a mixture of two graphite phases forms: the first is turbostratic graphite with d002 = 3.38 Å; the second is compressed graphite with d002 = 3.21 Å. On heating a particle to 1960 °C graphite is formed in which the layer packing contains a large amount of defects and is a mixture of 2Н and 3R polytypes (the ratio 40:60) with a small degree of turbostratic disordering.
KW - compressed graphite
KW - diamond
KW - graphite
KW - impact diamond
KW - lonsdaleite
KW - mixed-layered graphite
KW - simulation
KW - turbostratic disordering
KW - TRANSFORMATION
KW - HIGH-PRESSURE
KW - POWDER DIFFRACTION PATTERNS
KW - SIMULATION
KW - GRAPHITIZATION
UR - http://www.scopus.com/inward/record.url?scp=85048169376&partnerID=8YFLogxK
U2 - 10.1134/S0022476618020142
DO - 10.1134/S0022476618020142
M3 - Article
AN - SCOPUS:85048169376
VL - 59
SP - 355
EP - 364
JO - Journal of Structural Chemistry
JF - Journal of Structural Chemistry
SN - 0022-4766
IS - 2
ER -
ID: 13794916