def GBSAOBC2Force(solventDielectric=78.5, soluteDielectric=1, SA=None):
custom = CustomGBForce()
custom.addPerParticleParameter("q");
custom.addPerParticleParameter("radius");
custom.addPerParticleParameter("scale");
custom.addGlobalParameter("solventDielectric", solventDielectric);
custom.addGlobalParameter("soluteDielectric", soluteDielectric);
custom.addGlobalParameter("offset", 0.009)
custom.addComputedValue("I", "step(r+sr2-or1)*0.5*(1/L-1/U+0.25*(r-sr2^2/r)*(1/(U^2)-1/(L^2))+0.5*log(L/U)/r);"
"U=r+sr2;"
"L=max(or1, D);"
"D=abs(r-sr2);"
"sr2 = scale2*or2;"
"or1 = radius1-offset; or2 = radius2-offset", CustomGBForce.ParticlePairNoExclusions)
custom.addComputedValue("B", "1/(1/or-tanh(psi-0.8*psi^2+4.85*psi^3)/radius);"
"psi=I*or; or=radius-offset", CustomGBForce.SingleParticle)
custom.addEnergyTerm("-0.5*138.935485*(1/soluteDielectric-1/solventDielectric)*q^2/B", CustomGBForce.SingleParticle)
if SA=='ACE':
custom.addEnergyTerm("28.3919551*(radius+0.14)^2*(radius/B)^6", CustomGBForce.SingleParticle)
elif SA is not None:
raise ValueError('Unknown surface area method: '+SA)
custom.addEnergyTerm("-138.935485*(1/soluteDielectric-1/solventDielectric)*q1*q2/f;"
"f=sqrt(r^2+B1*B2*exp(-r^2/(4*B1*B2)))", CustomGBForce.ParticlePairNoExclusions)
return custom
def GBSAOBC2Force(solventDielectric=78.5, soluteDielectric=1, SA=None):
custom = CustomGBForce()
custom.addPerParticleParameter("q");
custom.addPerParticleParameter("radius");
custom.addPerParticleParameter("scale");
custom.addGlobalParameter("solventDielectric", solventDielectric);
custom.addGlobalParameter("soluteDielectric", soluteDielectric);
custom.addGlobalParameter("offset", 0.009)
custom.addComputedValue("I", "step(r+sr2-or1)*0.5*(1/L-1/U+0.25*(r-sr2^2/r)*(1/(U^2)-1/(L^2))+0.5*log(L/U)/r);"
"U=r+sr2;"
"L=max(or1, D);"
"D=abs(r-sr2);"
"sr2 = scale2*or2;"
"or1 = radius1-offset; or2 = radius2-offset", CustomGBForce.ParticlePairNoExclusions)
custom.addComputedValue("B", "1/(1/or-tanh(psi-0.8*psi^2+4.85*psi^3)/radius);"
"psi=I*or; or=radius-offset", CustomGBForce.SingleParticle)
custom.addEnergyTerm("-0.5*138.935485*(1/soluteDielectric-1/solventDielectric)*q^2/B", CustomGBForce.SingleParticle)
if SA=='ACE':
custom.addEnergyTerm("28.3919551*(radius+0.14)^2*(radius/B)^6", CustomGBForce.SingleParticle)
elif SA is not None:
raise ValueError('Unknown surface area method: '+SA)
custom.addEnergyTerm("-138.935485*(1/soluteDielectric-1/solventDielectric)*q1*q2/f;"
"f=sqrt(r^2+B1*B2*exp(-r^2/(4*B1*B2)))", CustomGBForce.ParticlePairNoExclusions)
return custom
def GBSAGBnForce(solventDielectric=78.5, soluteDielectric=1, SA=None):
"""
Indexing for tables:
input: radius1, radius2
index = (radius2*200-20)*21 + (radius1*200-20)
output: index of desired value in row-by-row, 1D version of Tables 3 & 4
"""
custom = CustomGBForce()
custom.addPerParticleParameter("q");
custom.addPerParticleParameter("radius");
custom.addPerParticleParameter("scale");
custom.addGlobalParameter("solventDielectric", solventDielectric);
custom.addGlobalParameter("soluteDielectric", soluteDielectric);
custom.addGlobalParameter("offset", 0.009)
custom.addGlobalParameter("neckScale", 0.361825)
custom.addGlobalParameter("neckCut", 0.68)
custom.addFunction("getd0", d0, 0, 440)
custom.addFunction("getm0", m0, 0, 440)
custom.addComputedValue("I", "Ivdw+neckScale*Ineck;"
"Ineck=step(radius1+radius2+neckCut-r)*getm0(index)/(1+100*(r-getd0(index))^2+0.3*1000000*(r-getd0(index))^6);"
"index = (radius2*200-20)*21 + (radius1*200-20);"
"Ivdw=step(r+sr2-or1)*0.5*(1/L-1/U+0.25*(r-sr2^2/r)*(1/(U^2)-1/(L^2))+0.5*log(L/U)/r);"
"U=r+sr2;"
"L=max(or1, D);"
"D=abs(r-sr2);"
"sr2 = scale2*or2;"
"or1 = radius1-offset; or2 = radius2-offset", CustomGBForce.ParticlePairNoExclusions)
custom.addComputedValue("B", "1/(1/or-tanh(1.09511284*psi-1.907992938*psi^2+2.50798245*psi^3)/radius);"
"psi=I*or; or=radius-offset", CustomGBForce.SingleParticle)
custom.addEnergyTerm("-0.5*138.935485*(1/soluteDielectric-1/solventDielectric)*q^2/B", CustomGBForce.SingleParticle)
if SA=='ACE':
custom.addEnergyTerm("28.3919551*(radius+0.14)^2*(radius/B)^6", CustomGBForce.SingleParticle)
elif SA is not None:
raise ValueError('Unknown surface area method: '+SA)
custom.addEnergyTerm("-138.935485*(1/soluteDielectric-1/solventDielectric)*q1*q2/f;"
"f=sqrt(r^2+B1*B2*exp(-r^2/(4*B1*B2)))", CustomGBForce.ParticlePairNoExclusions)
return custom
def GBSAGBnForce(solventDielectric=78.5, soluteDielectric=1, SA=None):
"""
Indexing for tables:
input: radius1, radius2
index = (radius2*200-20)*21 + (radius1*200-20)
output: index of desired value in row-by-row, 1D version of Tables 3 & 4
"""
custom = CustomGBForce()
custom.addPerParticleParameter("q");
custom.addPerParticleParameter("radius");
custom.addPerParticleParameter("scale");
custom.addGlobalParameter("solventDielectric", solventDielectric);
custom.addGlobalParameter("soluteDielectric", soluteDielectric);
custom.addGlobalParameter("offset", 0.009)
custom.addGlobalParameter("neckScale", 0.361825)
custom.addGlobalParameter("neckCut", 0.68)
custom.addFunction("getd0", d0, 0, 440)
custom.addFunction("getm0", m0, 0, 440)
custom.addComputedValue("I", "Ivdw+neckScale*Ineck;"
"Ineck=step(radius1+radius2+neckCut-r)*getm0(index)/(1+100*(r-getd0(index))^2+0.3*1000000*(r-getd0(index))^6);"
"index = (radius2*200-20)*21 + (radius1*200-20);"
"Ivdw=step(r+sr2-or1)*0.5*(1/L-1/U+0.25*(r-sr2^2/r)*(1/(U^2)-1/(L^2))+0.5*log(L/U)/r);"
"U=r+sr2;"
"L=max(or1, D);"
"D=abs(r-sr2);"
"sr2 = scale2*or2;"
"or1 = radius1-offset; or2 = radius2-offset", CustomGBForce.ParticlePairNoExclusions)
custom.addComputedValue("B", "1/(1/or-tanh(1.09511284*psi-1.907992938*psi^2+2.50798245*psi^3)/radius);"
"psi=I*or; or=radius-offset", CustomGBForce.SingleParticle)
custom.addEnergyTerm("-0.5*138.935485*(1/soluteDielectric-1/solventDielectric)*q^2/B", CustomGBForce.SingleParticle)
if SA=='ACE':
custom.addEnergyTerm("28.3919551*(radius+0.14)^2*(radius/B)^6", CustomGBForce.SingleParticle)
elif SA is not None:
raise ValueError('Unknown surface area method: '+SA)
custom.addEnergyTerm("-138.935485*(1/soluteDielectric-1/solventDielectric)*q1*q2/f;"
"f=sqrt(r^2+B1*B2*exp(-r^2/(4*B1*B2)))", CustomGBForce.ParticlePairNoExclusions)
return custom
