TY - JOUR
T1 - Sign Switch of Gaussian Bending Modulus for Microemulsions
T2 - A Self-Consistent Field Analysis Exploring Scale Invariant Curvature Energies
AU - Varadharajan, Ramanathan
AU - Leermakers, Frans A.M.
PY - 2018/1/10
Y1 - 2018/1/10
N2 - Bending rigidities of tensionless balanced liquid-liquid interfaces as occurring in microemulsions are predicted using self-consistent field theory for molecularly inhomogeneous systems. Considering geometries with scale invariant curvature energies gives unambiguous bending rigidities for systems with fixed chemical potentials: the minimal surface Im3m cubic phase is used to find the Gaussian bending rigidity κ̄, and a torus with Willmore energy W=2π2 allows for direct evaluation of the mean bending modulus κ. Consistent with this, the spherical droplet gives access to 2κ+κ̄. We observe that κ̄ tends to be negative for strong segregation and positive for weak segregation, a finding which is instrumental for understanding phase transitions from a lamellar to a spongelike microemulsion. Invariably, κ remains positive and increases with increasing strength of segregation.
AB - Bending rigidities of tensionless balanced liquid-liquid interfaces as occurring in microemulsions are predicted using self-consistent field theory for molecularly inhomogeneous systems. Considering geometries with scale invariant curvature energies gives unambiguous bending rigidities for systems with fixed chemical potentials: the minimal surface Im3m cubic phase is used to find the Gaussian bending rigidity κ̄, and a torus with Willmore energy W=2π2 allows for direct evaluation of the mean bending modulus κ. Consistent with this, the spherical droplet gives access to 2κ+κ̄. We observe that κ̄ tends to be negative for strong segregation and positive for weak segregation, a finding which is instrumental for understanding phase transitions from a lamellar to a spongelike microemulsion. Invariably, κ remains positive and increases with increasing strength of segregation.
U2 - 10.1103/PhysRevLett.120.028003
DO - 10.1103/PhysRevLett.120.028003
M3 - Article
AN - SCOPUS:85040454706
SN - 0031-9007
VL - 120
JO - Physical Review Letters
JF - Physical Review Letters
IS - 2
M1 - 028003
ER -