. 2022 Aug 23;126(34):6575–6584. doi: 10.1021/acs.jpcb.2c03923

Table 1. Characteristics of SiO₂ and Core–Shell (SiO₂–PMMA) Infiltrated Opals, Deduced from Experiments.

sample code (S-d, S-P-d)^a	particle diameter d (nm)	SiO₂ volume fraction ϕ^c	effective-medium sound velocity in the PDMS-infiltrated opals c_eff (m/s)^d	particle vibration in air f(1, 2) (GHz)	particle vibration in PDMS f(1, 2) (GHz)
S-143	143	1	2020	19.5	19
S-219	219	1	1670^e		11.2^e
S-227	227	1	1960
S-375	375	1	1690^e		5.9^e
S-181	181	1	1980	13^g	12.4
S–P-232^b	232	0.47	1800	10.3^g	9.4
S–P-294^b	294	0.23	≤1530^f	6.3^g	5.3
S–P-405^b	405	0.09	≤1560^f	3.9^g	3.8

S: SiO₂. P: PMMA. d: particle diameter.

d_SiO2 = 181 nm.

ϕ = (d_SiO2/d)³.

Error ±2%.

Particles in liquid SR256 matrix³³

q-range not sufficiently low

Ref (34).

Table 1. Characteristics of SiO2 and Core–Shell (SiO2–PMMA) Infiltrated Opals, Deduced from Experiments.