physical gels and strong liquids 5th international discussion meeting on relaxations in complex...
Post on 21-Dec-2015
219 views
TRANSCRIPT
![Page 1: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/1.jpg)
Physical Gels and strong liquids
5th International Discussion Meeting on Relaxations in Complex SystemsNew results, Directions and Opportunities
Francesco Sciortino
Wednesday … last talk
![Page 2: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/2.jpg)
Outline
• Irreversible (Chemical) Gelation in a simple model
• Thermoreversible (Physical) Gelation
• Gels (strong liquids) and Glasses
• Other gels…..(water, DNA-gels)
![Page 3: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/3.jpg)
V(r)
r
Simple Model for Chemical Gels [with HS g(r)]
Irreversible Gelation
![Page 4: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/4.jpg)
Behavior of the density autocorrelation functions
dependence
![Page 5: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/5.jpg)
Irreversible Gelation fq
Signatures of percolation at fixed q
![Page 6: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/6.jpg)
Finite Lifetime….V(r)
r
See also Del Gado works
![Page 7: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/7.jpg)
Generic Phase Diagram for Square Well (3%)
What on cooling ?
![Page 8: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/8.jpg)
The dream
![Page 9: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/9.jpg)
The quest for the ideal (thermoreversible) gel….model1) Long Living (but reversible)
bonds2)No Phase Separation
Are 1 and 2 mutually exclusive ?
LowTemperature
Condensation
Long Bond Lifetime
The quest
![Page 10: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/10.jpg)
Surface Tension
How to stay at low T without condensation ?
Reasons for condensation (Frank, Hill, Coniglio)
Physical Clusters at low T
if the infinite cluster is the lowest (free)energy state
How to make the surface as stable as the bulk (or more)?
![Page 11: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/11.jpg)
E=0 E=-NmaxE=-1 E=-Nmax
Nmax on a Bethe lattice
S.Sastry and E. La Nave
max
max
max
![Page 12: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/12.jpg)
Geometric Constraint: Maximum Valency
SW if # of bonded particles <= Nmax
HS if # of bonded particles > Nmax
V(r)
r
![Page 13: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/13.jpg)
Phase Diagram
et al
![Page 14: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/14.jpg)
It is possible to equilibrate at low T !
![Page 15: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/15.jpg)
The structure of the gel
![Page 16: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/16.jpg)
What is the gel dynamics (in this model) ?
• Bond lifetime (Arrhenius along isochores)
![Page 17: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/17.jpg)
What is the gel dynamics (in this model) ?
• Bond lifetime
• R2 vs t (along isochores)
![Page 18: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/18.jpg)
Gel vs Glass - MSD
![Page 19: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/19.jpg)
What is the gel dynamics (in this model) ?• Bond lifetime
• R2 vs t
• Fq(t)
![Page 20: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/20.jpg)
D along isochores… D along isoterms
![Page 21: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/21.jpg)
Dynamic Arrest Lines
The possibility of observing strong-liquid behavior intimately connected to reduction of bonding
![Page 22: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/22.jpg)
Pair-wise model (geometric correlation between bonds) (PMW, I. Nezbeda)
![Page 23: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/23.jpg)
Colloidal Gels, Molecular Gels, …. and DNA gels
Four Arm Ologonucleotide Complexes as precursors for the generation of supramolecular periodic assembliesJACS 126, 2050 2004
Palindroms in complementary space
![Page 24: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/24.jpg)
![Page 25: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/25.jpg)
Conclusions…..
• Gel propensity: Initial understanding of the ingredients requested to generate an “ideal” gel
• Gels and Glasses (two different faces of the arrest dynamics). Percolation not seen…
• Molecular and Atomic gels - Strong ! • Interesting questions…. Where is the MCT
line ?
![Page 26: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/26.jpg)
C. De Michele, E. La Nave, P. Tartaglia, E. Zaccarelli (U. La Sapienza, Roma, Italy)
I. Saika-Voivod (U. Saskatchewan, Canada)
A. Moreno (Donostia International Center, Spain)
S. Bulderyev (DMD code) (Yeshiva U., USA)
S. Sastry (Bethe) (JNCASR, India)
F. Starr (DNA-Gels) (Wesleyan U., USA)
![Page 27: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/27.jpg)
Gel vs Glass: Density Autocorrelation Functions
fq
![Page 28: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/28.jpg)
Fq gel vs glass
![Page 29: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/29.jpg)
Bond Lifetime.. Several more decades..
![Page 30: Physical Gels and strong liquids 5th International Discussion Meeting on Relaxations in Complex Systems New results, Directions and Opportunities Francesco](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d6a5503460f94a48b6f/html5/thumbnails/30.jpg)