name = 'diamond4carbon'

C1 = Atom('C')
C2 = Atom('C')
C3 = Atom('C')
C4 = Atom('C')

b12 = Bond(C1,C2)
b23 = Bond(C2,C3)
b34 = Bond(C3,C4)

da1 = Dihedral(C1,C2,C3,C4,180*deg)

amber_atom_type = {C1: 'CT', C2: 'CT', C3: 'CT', C4: 'CT' }
#mm3_atom_type = {C1: 1, C2: 1, C3: 1, C4: 1 }

dC1a = DanglingBond(C1, Dihedral(None,C1,C2,C3, 60*deg))
dC1b = DanglingBond(C1, Dihedral(None,C1,C2,C3,-60*deg))
dC1c = DanglingBond(C1, Dihedral(C3,C2,C1,None,180*deg))
dC2a = DanglingBond(C2, Dihedral(None,C2,C3,C4,-60*deg))
dC2b = DanglingBond(C2, Dihedral(None,C2,C3,C4, 60*deg))
dC3a = DanglingBond(C3, Dihedral(C1,C2,C3,None, 60*deg))
dC3b = DanglingBond(C3, Dihedral(None,C3,C2,C1,-60*deg))
dC4a = DanglingBond(C4, Dihedral(C2,C3,C4,None, 60*deg))
dC4b = DanglingBond(C4, Dihedral(C2,C3,C4,None,-60*deg))
dC4c = DanglingBond(C4, Dihedral(C2,C3,C4,None,180*deg))

hooknorth = Hook(None, [dC1c])
hooksouth = Hook(None, [dC4c])
hookup   = Hook(None, [dC2b, dC4b])
hookdown = Hook(None, [dC1a, dC3b])
hookeast = Hook(None, [dC2a, dC4a])
hookwest = Hook(None, [dC1b, dC3a])