# FEASST particle file (https://doi.org/10.18434/M3S095)
# EPM2 CO2 https://doi.org/10.1021/j100031a034
#
# The sigma_C-O mixing rule is not the default LB but instead geometric sqrt(sigma_C sigma_O).
# This must be input manually into FEASST the Configuration argument "sigma0_1 2.89170901025674"
#
# Oxygen(index 1, type 1) - Carbon(index 0, type 0) - Oxygen (index 2, type 1)
#
# Harmonic angle potential is k(theta - theta_0)^2, without the 1/2 factor (see AngleHarmonic).
# The original manuscript reports drawing from an angle distribution with probability
#
# P(theta) = exp[-0.5 beta kappa (theta - theta_0)]
#
# in the fourth paragraph of the manuscript.
# The correct distribution should have been
#
# P(theta) = sin(theta)*exp[-0.5 beta kappa (theta - theta_0)]
#
# Because for k=0, P(theta) = sin(theta) for random point picking on the surface of a unit sphere.
# The reported distribution leads to unphysical bias toward the poles (theta 0 and pi).
# This may have led other researchers to implement a rigid version of EPM2, because the
# bias toward the poles makes the bond more stiff than if the sin(theta) term was included.
# Therefore, a rigid approximation may not be a terrible choice.
# In this spirit, we have removed the following commented lines to make this a rigid model.
#
# 2 bonds
# 1 angles
#
# 1 bond types
# 1 angle types
#
# Bond Properties
#
# 0 RigidBond length 1.149 delta 0.000001
#
# Bonds
#
# 0 0 0 1
# 1 0 0 2
#
# Angle Properties
#
# 0 AngleHarmonic equilibrium_degrees 180.0 k_energy_per_radian_sq 618
#
# Angles
#
# 0 0 1 0 2
#
# Units
# length: Angstrom
# energy: kJ/mol
# charge: elementary

Site Properties

0 sigma=2.757 epsilon=0.2338775189860325 cutoff=14.0 charge=0.6512 cutoff_outer=1.149
1 sigma=3.033 epsilon=0.669372441999663 cutoff=14.0 charge=-0.3256 cutoff_outer=1.149

Sites

0 0  0     0 0
1 1 -1.149 0 0
2 1  1.149 0 0
