TY  - CONF
AU  - Kang, Kyongok
TI  - Non-equilibrium and Equilibrium Phase behaviour of Charged Colloidal Rods (DNA-rods)
M1  - FZJ-2024-04001
PY  - 2024
N1  - The DFG Grant number is acknowledged as KA 5628/2-1.
AB  - Both non-equilibrium (in electric-field and shear flow) [1-3] and equilibrium phase behaviour [4-7] are presented for the concentrated suspensions of charged DNA-viruses at the low ionic strength of Tris/HCl buffer. The system is revealed as a good model system of charged colloidal rods (DNA-rods) to predict the phase transitions, from the nematic-to-chiral nematic and other hierarchical chiral-mesophases (X-pattern and helical domains) to the (structural) glass states, in an increase of the rod-concentration [4-6]. In last 2 decades, several instrumentations and methods are developed with characterizations in both signal-and image-processing (under external fields) to access wide ranges of multiple phases and various transitions, dynamics, and kinetics of the interacting charged DNA-rods.Recently, as one of interesting findings for chiral-mesophases, the long-time existing X-pattern is turned out to be the subclass of “chiral-glass”, shown by the replica symmetry breaking (RSB), determined by both real- and Fourier-space [6]. This X-pattern occurs interestingly between the two “replicas” of larger chiral-nematic domain (at a lower concentration) and the “helical-domains” (at a higher concentration) of charged DNA-rods [7]. Further interest is then the order parameter in phase transitions, by dissociation/association of condensed ions in the mean-field approach (via ionic-strength dependent effective Debye screening length and the concentration), as well as the competition between the averaged orientation of concentrated rods and the strength of local ordering of helical domains. The concentration (or the number density) and orientation are coupled via effective diameter in the chiral-mesophase behavior.References[1] K. Kang and J.K.G. Dhont, “An electric-field induced dynamical state in dispersions of highly charged colloidal rods: Comparison of experiment and theory”, Colloid. Polym. Sci. 293, 3325-3336, 2015.[2] K. Kang, “Response of shear in bulk orientations of charged DNA rods: Taylor- and Gradient-banding”, J. Phys. Commun, 5, 045011, 2021.[3] D. Parisi, D. Vlassopoulos, H. Kriegs, J. K. G. Dhont, and K. Kang, “Underlying mechanism of shear-banding in soft glasses of charged colloidal rods with orientational domains”, Journal of Rheology 66, 365, 2022.[4] K. Kang, “Glass transition of repulsive charged rods (fd-viruses)”, Soft Matter, 10, 3311-3324, 2014.[5] K. Kang, “Equilibrium phase diagram and thermal responses of charged DNA-virus rod-suspensions at low ionic strengths”, Sci. Rep. 11: 3472, 2021.[6] K. Kang, “Chiral glass of charged DNA rods, Cavity loops”, J. Phys. Commun, 5, 065001, 2021.[7] K. Kang, “Characterization of orientation correlation kinetics: chiral-mesophase domains in suspensions charged DNA-rods”, J. Phys. Commun, 6, 015001, 2022.
T2  - SoftComp 20th Anniversary Meeting
CY  - 21 May 2024 - 24 May 2024, Hotel Valpre, Lyon (France)
Y2  - 21 May 2024 - 24 May 2024
M2  - Hotel Valpre, Lyon, France
LB  - PUB:(DE-HGF)6
UR  - https://juser.fz-juelich.de/record/1027683
ER  -