c! Variable Declarations
c! Charge of i-th residue, charge of j-th residue,...
      INTEGER Qi, Qj, Qij, ii, jj, itypi, itypj

c! STUFF FROM EMOMO

c! why do *I* have to declare those guys, when it is used throughout the whole code...
      REAL*8 evdw, evdw_p, evdw_m
      double precision xi, yi, zi, ctail(3,2), chead(3,2)
c! FOLLOWING ARE ***NOT*** in common block!!!
c! They are here just for their declarations
      REAL*8 ecl,elj,equad,epol
      INTEGER istate
c! intermediates
      REAL*8 c1, c2, fac, pom
c! switch in the selector choosing which electrostatic energy/gradient function to call
      INTEGER isel
c! sigma factors
      REAL*8 sig, sig0ij, sig1, sig2
c! intermediates related to distance
      REAL*8 rij_shift, rrij, R1, R2, RR1, RR2
c! intermediates related to angles
      REAL*8 sinth1sq, sinth2sq
c! intermediates of Fgb
      REAL*8 fgb, ee, ee1, ee2, eps0, pis

c! squares of om1, om2 and om12 (those hold cosines of angles
c! theta)
      REAL*8 sqom1, sqom2, sqom12

c! Geometry and general stuff
c! a12sq = ai*aj from fgb which is present in Egbpol/Fgbpol,
c! Epol/Gpol and others, ee is an intermediate.
c! three dimensions for X, Y and Z Cartesians
      REAL*8 a12sq

c! square distance and cartesian distances of polar/charged heads of sidechains
      REAL*8 Rhead, Rhead_distance(3), Rhead_sq
c! square distance and cartesian distances of tail(hydrophobic centre of interaction)
c! of a given pair of sidechains
      REAL*8 Rtail, Rtail_distance(3)
c! intermediates used in dXhead/dXtail
      REAL*8 erhead(3), ertail(3), facd1, facd2, erdxi, erdxj

c! unit vectors used to calculate R's
      REAL*8 d1sq, d2sq, d1d2
      REAL*8 d1, d2

c! intermediates (hold different meanining in different places)
      REAL*8 bat, hawk, eagle, condor, sparrow, rosella
      REAL*8 tuna(3)

c! holds 1/eps_in - 1/eps_out which appears in EGBpol Makowski et al JPCB 2011
c! p. 6122
      REAL*8 eps_inout_fac, eps_in

c! DERIVATIVES
c! intermediates
      Real*8 dFdR, dFdL, dFdOM1, dFdOM2, dFdOM12
c! Kronecker Delta used for dXhead/dXtail derivatives
      Real*8 kro_delta
c! Gcl
      REAL*8 Gelconst
      REAL*8 dGCLdR, dGCLdOM1, dGCLdOM2, dGCLdOM12

c! Ggbpol
c! energy
      REAL*8 Egb, dGGBdFGB, dGGBdR
      REAL*8 dFGBdR, alphapol1, alphapol2

c! Gpol
      REAL*8 fgb1, fgb2
      REAL*8 dPOLdOM1, dPOLdOM2, dPOLdR1, dPOLdR2
      REAL*8 dFGBdOM1, dFGBdOM2, dFGBdR1, dFGBdR2
      REAL*8 dPOLdFGB1, dPOLdFGB2, MomoFac1, MomoFac2
      REAL*8 erhead_tail(3,2)

c! Gisocav
      REAL*8 Fisocav, dGCVdR
c! alpha parameters for Fisocav/Gisocav
      REAL*8 al1, al2, al3, al4, csig

c! Gcav
c! energy
      REAL*8 Fcav
c! alphas from the equation
      REAL*8 b1, b2, b3, b4
c! intermediates
      Real*8 chif, lambf, chilambf
      REAL*8 top, bot, dtop, dbot, botsq
      REAL*8 chis1, chis2, chis12
c! final value
      REAL*8 dCAVdOM1, dCAVdOM2, dCAVdOM12

c! Gquad stuff
c! intermediates
      REAL*8 wqd, w1, w2, beta1
c! final value
      REAl*8 dQUADdR, dQUADdOM1, dQUADdOM2, dQUADdOM12

c! Glj
c! parameter, radial derivative
      REAL*8 eps_head, dGLJdR

c! Sum of states
      REAL*8 BetaT, eheadtail, weightbol, sumweight
c! this thing holds intermediates and final value
c! (dimensions, gvdw(c/x)(i/j),intermediate(1) or final(2))
      REAL*8 gheadtail(3,4,2)

c! Now Commonize what we need to
      COMMON /emp/ Qi, Qj, Qij, ii, jj, itypi, itypj, xi, yi, zi
     & , sqom1, sqom2, sqom12, chead, ctail
     & , al1, al2, al3, al4
     & , b1, b2, b3, b4
     & , Rhead, Rhead_distance, Rtail, Rtail_distance
     & , R1, R2, RR1, RR2
     & , d1sq, d2sq, d1, d2, d1d2
     & , eps_inout_fac, eps_in, wqd, eps_head, a12sq
     & , chis1, chis2, chis12, sig1, sig2, sig0ij
     & , BetaT
     & , dFdR, dFdL, dFdOM1, dFdOM2, dFdOM12
     & , dCAVdOM1, dCAVdOM2, dCAVdOM12
     & , dGCLdOM1, dGCLdOM2, dGCLdOM12
     & , dPOLdOM1, dPOLdOM2
     & , dQUADdR, dQUADdOM1, dQUADdOM2, dQUADdOM12