TY - JOUR
T1 - Fluctuations in symmetric diblock copolymers
T2 - Testing theories old and new
AU - Qin, Jian
AU - Morse, David C.
PY - 2012/6/6
Y1 - 2012/6/6
N2 - Computer simulations are used to study composition fluctuations in disordered diblock copolymer melts over a range of values of the chain length N, and test several theories for the structure factor S(q). Specifically, we test the random-phase approximation (RPA), which is based on a self-consistent field treatment of fluctuations, the Fredrickson-Helfand theory, which was designed to describe fluctuations near the order-disorder transition, and the relatively new renormalized one-loop (ROL) theory. The results confirm claims that the RPA is exact in the limit N→ and that the ROL theory yields the dominant corrections to the RPA within a systematic expansion in powers of N -1 /2, and show that the ROL theory is much more accurate than either older theory.
AB - Computer simulations are used to study composition fluctuations in disordered diblock copolymer melts over a range of values of the chain length N, and test several theories for the structure factor S(q). Specifically, we test the random-phase approximation (RPA), which is based on a self-consistent field treatment of fluctuations, the Fredrickson-Helfand theory, which was designed to describe fluctuations near the order-disorder transition, and the relatively new renormalized one-loop (ROL) theory. The results confirm claims that the RPA is exact in the limit N→ and that the ROL theory yields the dominant corrections to the RPA within a systematic expansion in powers of N -1 /2, and show that the ROL theory is much more accurate than either older theory.
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U2 - 10.1103/PhysRevLett.108.238301
DO - 10.1103/PhysRevLett.108.238301
M3 - Article
AN - SCOPUS:84861907146
SN - 0031-9007
VL - 108
JO - Physical review letters
JF - Physical review letters
IS - 23
M1 - 238301
ER -