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  3. Volume 10, Number 2, 2020
  4. Calculation of the phase state of the [N(CH3)4]2CUCL4 crystals

Calculation of the phase state of the [N(CH3)4]2CUCL4 crystals

JCPEE.
2020;
Volume 10, Number 2
: pp. 28-32
https://doi.org/10.23939/jcpee2020.02.028
Authors:
  1. Sergii Sveleba
  2. Ivan Katerynchuk
  3. Ivan Kuno
  4. Ivan Karpa
  5. Ostap Semotiuk
  6. Volodymyr Brygilevych
1
Ivan Franko National University of Lviv
2
Ivan Franko National University of Lviv
3
Ivan Franko National University of Lviv
4
Ivan Franko National University of Lviv
5
Ukrainian Academy of Printing
6
Institute of Technical Engineering the State Higher School of Technology and Economics in Jarosław

The calculation of the spatial changes of the amplitude and phase of the order parameter was performed in the Python environment with the use of the Skipy and JiTCODE libraries.

In [N(CH3)4]2CuCl4 crystals, there is an incommensurate phase I1 at the small values of the magnitude of long-range interaction (T<0.6) and an incommensurate phase I2 at T≥1.0. This is the same incommensurate phase, although the behavior of the amplitude and phase functions in it is different under the different conditions mentioned above. At T = 0.6 ÷ 1.0, the coexistence of these two phases is observed which is manifested in the absence of anomalous changes of q during the transition from the sinusoidal mode of IC modulation to the soliton regime

lyapunov’s exponents; the incommensurate superstructure; surface energy
backward differentiation formula (BDF) method
python
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