Browse By Author Name - Iacovella, Christopher R. - Fez

Yukawa potential

Iacovella, Christopher R. — Wed, 16 Apr 2008 19:36:36

Plot of the Yukawa potential showing the hard=core formulation of the Yukawa Potential for several combinations of ε and κ. The Yukawa pair potential is used to model the interaction between charge stabilized colloids. It is a purely repulsive potential when considered two particles with like charge; oppositely charged particles will exhibit an attraction.

Weeks-Chandler-Andersen potential (WCA)

Iacovella, Christopher R. — Wed, 16 Apr 2008 18:34:50

The Weeks-Chandler-Andersen potential (WCA) is a short range, purely repulsive interaction potential. It is meant to model excluded volume interaction and short range repulsion.

Velocity autocorrelation function (VACF) statistics

Iacovella, Christopher R. — Wed, 16 Apr 2008 18:34:34

The diffusion coefficient as calculated from the velocity autocorrelation function (VACF) for 4000 timesteps and 40000 timesteps.

Tethered Sphere Bilayers 2

Iacovella, Christopher R. — Thu, 21 Sep 2006 12:16:11

Simulation Software:Glotzer Group Code Slow Cooling from a high temperature disorded state to a final state with dimensionless temperature of 2.0 with an overall volume fraction of 0.40 System being modeled:polymer tethered nanosphere Model used to describe the system:United Atom Bead Spring with Lennard Jones, WCA, and FENE Simulation method:Brownian Dynamics

Tethered Sphere Bilayer 1

Iacovella, Christopher R. og Horsch, Mark — Thu, 21 Sep 2006 11:56:48

System being modeled:polymer tethered nanosphere Simulation method:Brownian Dynamics Slow Cooling from a high temperature disorded state to a final state with dimensionless temperature of 4.0 with an overall volume fraction of 0.45 Simulation Software:Glotzer Group Code Model used to describe the system:United Atom Bead Spring with Lennard Jones, WCA, and FENE

Tethered sphere

Iacovella, Christopher R. — Wed, 16 Apr 2008 18:34:02

Tethered nanosphere cartoon.

Square-Well Potential and Lennard-Jones Potential

Iacovella, Christopher R. — Wed, 16 Apr 2008 18:33:47

Plot of the Square-Well Potential (SW) and Lennard-Jones Potential (LJ) showing The SW (solid) with LJ (dotted). The square-well potential is identical to the Hard Sphere Potential with the addition of an attractive well of depth.

Smectic C liquid crystal

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:50:11

Schematic of Smectic C liquid crystal.

Smectic A liquid crystal

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:49:54

Schematic of Smectic A liquid crystal.

Simple Cubic (SC) unit cell

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:49:39

Simple Cubic (SC) unit cell.

Radial Distribution Function (RDF) schematic

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:49:24

Schematic of the Radial Distribution Function (RDF). The radial distribution function, also known as RDF, g(r), or the pair correlation function, is a measure to determine the correlation between particles within a system. Specifically, it is a measure of, on average, the probability of finding a particle at a distance of r away from a given reference particle, relative to that for an ideal gas. The general algorithm involves determining how many particles are within a distance of r and r+dr away from a particle. This general theme is depicted in the schematic, where the red particle is our reference particle, and blue particles are those which are within the circular shell, dotted in red.

Polystyrene

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:49:15

Repeating structural unit of polystyrene.

Polymer Scaling Module

Iacovella, Christopher R. og Glotzer, Sharon C. — Tue, 16 Dec 2008 15:20:36

This simulation consists of a single-component system of particles that are permanently bonded together via Finitely extensible non-linear elastic (FENE) springs. Particles either interact via the Lennard-Jones Potential or the Weeks-Chandler-Andersen Potential to model different solvent selectivity. The system runs NVT Brownian Dynamics. The length of the polymer, solvent conditions, and runtime are all user-modifiable variables. The simulation outputs the end to end distance. Additional information is also provided such simulation model/method description, detailed instructions for running the simulation, tutorials, sample questions, literature examples, and links to other relevant data.

Polyhedral Oligomeric Silsesquioxane (POSS)

Iacovella, Christopher R. — Fri, 28 Mar 2008 02:00:01

Schematic of a Polyhedral Oligomeric Silsesquioxane (POSS) cage. POSS is made of silicon and oxygen atoms linked together in a cubic form, with silicon atoms occupying the corners. Commercially, POSS has many applications, such as: additive for heat and abrasion resistant paints; space resistant resins; precursors to ceramic matrices.

Periodic boundary conditions

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:23:31

Schematic of periodic boundary conditions. When using periodic boundary conditions, a particle which exits the system on the right, will reappear on the left. In the schematic, our simulation volume is colored in red. As the yellow particle exits on the right, it will re-enter on the left. This can be thought of as having identical simulation boxes surrounding the system. As the yellow particle enters the next simulation on the right, a particle from the periodic image on the left will enter.

Packing in rectilinear channels

Iacovella, Christopher R. — Tue, 22 Apr 2008 05:07:58

Renderings of simulations of particles confined within rectilinear channels. Simulations were performed using Brownian dynamics and a cosine potential in the Glotzilla simulation environment

Packing factor overview

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:22:56

Israelachvili Packing Factor Structural Trends.

Packing

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:23:20

Schematic of how surfactants pack.

NPT Molecular dynamics simulation of a Lennard-Jones monomer system

Iacovella, Christopher R. — Wed, 17 May 2006 09:22:08

Number of particles = 1000 ; System temperature as a function of time = 0.5; System pressure as a func of time = 10.0 ; Integration scheme to use = Molecular Dynamics, Martyna barostat, NPT; Timestep for integration of eqns of motion = 0.005; Number of Dimensions = 3 ;

Nematic liquid crystal

Iacovella, Christopher R. — Wed, 16 Apr 2008 16:44:53

Schematic of a nematic liquid crystal shown using rods.

Molecular Dynamics simulation of a Lennard-Jones solid

Iacovella, Christopher R. — Mon, 02 Oct 2006 17:10:59

Number of particles = 2000; System temperature = 0.5; System number density = 1.0; Integration scheme = Nose-Hoover, NVT; Number of Dimensions = 3; Time step = 0.01; Phase: FCC/HCP crystal;

Molecular Dynamics simulation of a Lennard-Jones liquid

Iacovella, Christopher R. — Mon, 02 Oct 2006 18:00:07

Number of particles = 500; System temperature = 1.0; System number density = 0.5; Integration scheme = Nose-Hoover, NVT; Number of Dimensions = 3; Time step = 0.01; Phase: Liquid;

Molecular Dynamics simulation of a Lennard-Jones gas

Iacovella, Christopher R. — Mon, 02 Oct 2006 17:27:59

Number of particles = 500; System temperature = 1.0; System number density = 0.01; Integration scheme = Nose-Hoover, NVT; Number of Dimensions = 3; Time step = 0.01; Phase: gas;

Molecular Dynamics (MD) Gas Module

Iacovella, Christopher R. og Glotzer, Sharon C. — Tue, 16 Dec 2008 14:40:37

This simulation consists of a single-component system of particles that interact as either ideal gas particles with no intermolecular potential or as Lennard-Jones Particles . The system runs NVT Molecular Dynamics utilizing the Berendsen Thermostat. The number of particles, volume and temperature are all user-modifiable variables. Additionally, one can select between non-interacting ideal gas particles or particles that interact via the Lennard-Jones Potential. The system can be changed between Argon and Krypton based on reduced unit variables. The average temperature and pressure are displayed on the screen. Additional information is also provided such simulation model/method description, detailed instructions for running the simulation, tutorials, sample questions, literature examples, and links to other relevant data.

Mean squared displacement (MSD) statistics

Iacovella, Christopher R. — Wed, 16 Apr 2008 16:44:43

How statistics influences the calculation of the diffusion coefficient from the Mean squared displacement.

Mean Squared Displacement (MSD) of a Lennard-Jones Fluid

Iacovella, Christopher R. — Thu, 27 Sep 2007 13:13:52

Plot of the Mean Squared Displacement (MSD) of a Lennard-Jones Fluid.
Number of particles = 1000;
System temperature = 2.0;
System number density = 0.85;
Integration scheme = Molecular dynamics Nose-Hoover, NVT;
Number of Dimensions = 3;
Timestep = 0.001;
Lennard-Jones;
Phase: Liquid;
Red line in plot corresponds to the data provided in MSD_lmp.txt and data.txt.gz.

Mean Squared Displacement (MSD)

Iacovella, Christopher R. — Wed, 16 Apr 2008 16:44:15

Mean Squared Displacement of an NVT Molecular dynamics simulation of Lennard-Jones particles at Number density of 0.85, and temperature of 2.0 and 0.5. Here N=1000.

Liquid Crystal

Iacovella, Christopher R. — Wed, 16 Apr 2008 16:02:47

Example of the difference between a crystal, liquid crystal, and liquid as displayed using rods.

Lennard-Jones Potential (LJ)

Iacovella, Christopher R. — Tue, 15 Apr 2008 19:46:23

Graph of the Lennard-Jones Potential (LJ). LJ is used to model the excluded volume interactions and van der Waals interaction attraction of neutral atoms.

Lennard-Jones Fluid Module Basic

Iacovella, Christopher R. og Glotzer, Sharon C. — Tue, 16 Dec 2008 14:56:15

This simulation consists of a single-component system of particles that interact via the Lennard-Jones Potential. The system runs NVT Molecular Dynamics using the Berendsen Thermostat. The number of particles, number density, and temperature are all user-modifiable variables. The simulation outputs the radial distribution function ( RDF) at the end of the simulation, and the average temperature to the screen.

Additional information is also provided such simulation model/method description, detailed instructions for running the simulation, tutorials, sample questions, literature examples, and links to other relevant data.

Lauryldimethylamine-oxide (LDAO)

Iacovella, Christopher R. — Wed, 16 Apr 2008 16:02:28

Lauryldimethylamine-oxide (LDAO) is an example of a common surfactant.

Israelachvili Packing factor

Iacovella, Christopher R. — Wed, 16 Apr 2008 17:23:08

Israelachvili Packing factor. The geometry of associated structures depends upon "packing" properties of the molecule: the optimal area of the head group, a0, volume of the chain, V, and the critical length of the tether, lc.

Inverted Micelle of Tethered Nanosphere

Iacovella, Christopher R. — Thu, 21 Sep 2006 10:39:49

A system of 14 building blocks of composition h1t12 at a concentration of 0.001, was run starting at an infinite temperature then instantaneously quenched to a temperature of 4.0. The system was then run for ~10^5 time steps forming a miceller structure. Simulation Method: Brownian Dynamics Simulation Software: Glotzer Group Code Simulation Model: United Atom Bead Spring with Lennard-Jones and FENE

Icosahedraon

Iacovella, Christopher R. — Wed, 16 Apr 2008 16:02:05

Particle representation of a icoshedral cluster formed by 13 Lennard-Jones particles using Molecular Dynamics.

Icosahedral packing of polymer-tethered nanospheres and stabilization of the Gyroid Phase

Wed, 20 Sep 2006 11:00:01

We present results of molecular simulations that predict the phases formed by the selfassembly of model nanospheres functionalized with a single polymer “tether”. Microphase separation of the immiscible tethers and nanospheres induces the formation of the double gyroid, perforated lamella and crystalline bilayer phases. Confinement effects promote the formation of icosahedral arrangements of nanoparticles that help to stabilize the gyroid and perforated lamella phases. We also present a new metric for determining the local arrangement of particles in liquid and solid configurations.
Preprint, link to published version can be found below.

Hexagonally Close Packed (HCP) unit cell

Iacovella, Christopher R. — Tue, 15 Apr 2008 18:50:14

Hexagonally Close Packed (HCP) unit cell.

Fluidic Assembly and Packing of Microspheres in Confined Channels

Tue, 22 Apr 2008 04:58:26

We study fluidic assembly and packing of spherical particles in rectilinear microchannels that are terminated by a flow constriction. First, we introduce a method for active assembly of particles in the confined microchannels by triggering a local constriction in the fluid channel using a partially closed membrane valve. This microfluidic valve allows active, on-demand particle assembly as opposed to previous passive assembly methods based on terminal channels and weirs. Second, we study the three-dimensional assembly and packing of particles against a weir in confined rectilinear microchannels. The packings result in achiral particle chains with alternating (zigzag) structure. This structure is characterized by a single, repeated bond angle whose components projected into the frame of the channel are quantified by confocal microscopy and image processing. Brownian dynamics simulation of the packing comprehensively delineates the range of bond angles possible in narrow, rectilinear microchannels as well as the complex dependence of these angles on the relative dimensions of the channel and particles. The simulations of the three-dimensional packings are accurately modeled by a compact theory based on trigonometric relationships. The experimentally measured bond angles show excellent agreement with the simulations, thereby validating the functional dependence of the achiral packing bond angles on channel dimensions. This functional relationship is immediately useful for the design of anisotropic particles by microfluidic synthesis.

Face Centered Cubic (FCC) unit cell

Iacovella, Christopher R. — Tue, 15 Apr 2008 13:33:04

Face Centered Cubic (FCC) unit cell, grey particles are face particles, red are corner particles. FCC is a type of close packed crystal lattice.

DPD Lamella formed by diblock copolymer

Iacovella, Christopher R. — Thu, 21 Sep 2006 09:42:44

A System of 1728 building blocks of composition A3B5 at a concentration of 5, was run starting at a disordered state at high temperature , then instantaneously quenched to a temperature of 1. The system was then run for 250000 time steps forming a sheets (lamella) phase. Delta A: 12 Simulation Software: Glotzer Group Code Simulation Method: Dissipative Particle Dynamics Simulation Model: DPD Particle Bead Spring with Soft Potential and FENE

DPD cylinders Time Evolution of diblock copolymer system

Iacovella, Christopher R. — Thu, 21 Sep 2006 10:06:56

A System of 2700 building blocks of composition 3 - 7 at a concentration of 5, was run starting at a disordered state at high temperature , then instantaneously quenched to a temperature of 1. The system was then run for 1000000 time steps forming a cylinders phase. Time evolution. Delta A: 6 Simulation Software: Glotzer Group Code Simulation Method: Dissipative Particle Dynamics Simulation Model: DPD Particle Bead Spring with Soft Potential and FENE

Dodecagonal quasicrystal

Iacovella, Christopher R. — Fri, 28 Mar 2008 01:59:51

Molecular Dynamics simulation of a Dzugutov system showing dodecagonal quasicrystalline behavior. Dodecagonal quasicrystals have 12-fold symmetry.

Dissipative Particle Dynamics simulation of a binary mixture

Iacovella, Christopher R. — Wed, 17 May 2006 09:13:24

Dissipative Particle Dynamics simulation of a binary mixture; classification=Binary Mixture; Number of particles=2000; System temperature as a func of time=1.0; System number density=5; DPD Epsilon = 30; Timestep for integration of eqns of motion=0.04; Integration scheme to use=Dissipative Particle Dynamics; Number of Spatial Dimensions=3;

Diblock copolymer phase diagram

Iacovella, Christopher R. — Tue, 15 Apr 2008 13:31:38

Adaptation of the Matsen and Bates BCP phase diagram predicted using Mean-field Theory. * Matsen MW, Bates FS, ''http://pubs3.acs.org/acs/journals/doilookup?in_doi=10.1021/ma951138i Unifying weak- and strong-segregation block copolymer theories. Diblock copolymer phase diagram as calculated using Mean-field Theory by Matsen and Bates, where fA is the Block fraction, χ is the Flory-Huggins Chi Parameter, and N is the length of the block.

Diamond unit cell

Iacovella, Christopher R. — Tue, 15 Apr 2008 13:32:22

Diamond unit cell.

Brownian Dynamics simulation of a tether-aggregating tethered nanosphere

Iacovella, Christopher R. — Wed, 17 May 2006 09:57:41

Number of tethered building blocks = 1300; Number of beads = 11700; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature as a func of time = 1.075; System volume fraction = 0.400; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE;

Brownian Dynamics simulation of a tether-aggregating tethered nanosphere

Iacovella, Christopher R. — Wed, 17 May 2006 09:54:48

Number of tethered building blocks = 1100; Number of beads = 9900; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature as a func of time = 1.212; System volume fraction = 0.375; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE;

Brownian Dynamics simulation of a tether-aggregating tethered nanosphere

Iacovella, Christopher R. — Wed, 17 May 2006 09:49:09

Number of tethered building blocks = 1000; Number of beads = 9000; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature as a func of time = 0.8; System volume fraction = 0.325; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE;

Brownian dynamics simulation of a tail-aggregating surfactant

Iacovella, Christopher R. — Wed, 17 May 2006 09:31:15

Number of polymers = 1000; Length of polymer chain = 10; Length of head group = 2; Number of beads = 10000; System number density = 0.865 ; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE;

Brownian Dynamics simulation of a nanoparticle-aggregating tethered nanosphere: perforated lamella

Iacovella, Christopher R. — Wed, 20 Sep 2006 15:29:59

Number of tethered building blocks = 800; Number of beads = 7200; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature = 0.3077; System volume fraction = 0.35; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE; Phase: Perforated lamella

Brownian Dynamics simulation of a nanoparticle-aggregating tethered nanosphere: lamellar bilayers

Iacovella, Christopher R. — Wed, 17 May 2006 09:44:01

Number of tethered building blocks = 500; Number of beads = 4500; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature as a func of time = 0.4; System volume fraction = 0.45; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE;

Brownian Dynamics simulation of a nanoparticle-aggregating tethered nanosphere: lamellar bilayers

Iacovella, Christopher R. — Wed, 17 May 2006 09:39:18

Number of tethered building blocks = 800; Number of beads = 7200; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature as a func of time = 0.275; System volume fraction = 0.25; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE;

Brownian Dynamics simulation of a nanoparticle-aggregating tethered nanosphere: lamellar bilayers

Iacovella, Christopher R. — Wed, 20 Sep 2006 15:23:40

Number of tethered building blocks = 500; Number of beads = 4500; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature = 0.3077; System volume fraction = 0.40; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE; Phase: Lamella

Brownian Dynamics simulation of a nanoparticle-aggregating tethered nanosphere: double gyroid

Iacovella, Christopher R. — Wed, 20 Sep 2006 15:18:39

Number of tethered building blocks = 500; Number of beads = 4500; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature = 0.3125; System volume fraction = 0.3; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE; Phase: Double Gyroid

Brownian Dynamics simulation of a nanoparticle-aggregating tethered nanosphere: cylindrical micelles

Iacovella, Christopher R. — Wed, 20 Sep 2006 15:14:05

Number of tethered building blocks = 800; Number of beads = 7200; Length of tether = 8; Diameter of the nanopshere = 2.0; System temperature = 0.2667; System volume fraction = 0.25; Integration scheme to use = Brownian Dynamics, NVT; Number of Dimensions = 3; United Atom Bead Spring with Lennard-Jones and FENE; Phase: Hexagonally packed cylindrical micelles

Bond angle of particles in small, rectilinear channels.

Iacovella, Christopher R. og Vanapalli, Siva A. — Tue, 22 Apr 2008 05:21:57

Comparison between experiment, simulations, and theory that predict the repeating bond angle for colloidal particles in small, rectilinear channels. Squares correspond to experiment (with aspect ratio labeled), circles correspond to simulation, and dashed lines correspond to theory. The dotted red line represents the phase boundary from zig-zag planar structures, to full 3d structures.

Body Centered Cubic (BCC) unit cell

Iacovella, Christopher R. — Tue, 15 Apr 2008 13:31:18

Body Centered Cubic (BCC) unit cell, red particles are corner particles, grey is a body particle.

Bead Spring Blocks

Iacovella, Christopher R. — Tue, 15 Apr 2008 13:31:53

Schematic of a simple model for the simulation of Block Copolymers and Surfactants. Image is a cartoon of 4-4, with a Block fraction fa = 0.5 bead spring representation of a block copolymer