function u=sosm(T,dd);
  
% General constants
R=8.314;
Tc=dd(1)+273.15;
rhoc=1/dd(2);
Pc=dd(3)*1e2;
mu0=dd(4)*1e-3;
Tb=dd(5)+273.15;
omega=dd(6);
R=8.314;
rg=dd(32)*1e10;
% DIPPR constants sets for temperature-dependent properties
RHOS=dd(8:12);
PS=dd(14:18);
LS=dd(20:24);
CS=dd(26:30);  

% Density
rhos=mu0*1e3*DIPPR105(RHOS,T);
Ps=DIPPR101(PS,T);
rhosb=mu0*1e3*DIPPR105(RHOS,Tb);

% Internal pressure at the boiling point
Pib=PiS(Tb,rhosb,omega,mu0);
 
% Isothermal compressibility
kk=-0.663*rg+0.0859*rg^2-0.00432*rg^3;
D=RHOS(4);
t=1-T/Tc;
Abet=-Tb*dlnDIPPR105(RHOS,Tb)/(Pib*exp(-2*(1-D)*log(1-Tb/Tc)+kk*(1-Tb/Tc)));
betaTs=exp(-2*(1-D)*log(t)+kk*t)*Abet;
 
% Isobaric expansion coefficient
dlnrhosdT=dlnDIPPR105(RHOS,T);
dPsdT=dDIPPR101(PS,T);
alphaPs=betaTs.*dPsdT-dlnrhosdT;
ind1=find(T<=Tb);
alphaPs(ind1)=-dlnrhosdT(ind1);

% Isobaric heat capacity
Cs=1e-3*DIPPR100(CS,T)/mu0;
Cps=Cs-alphaPs.*dPsdT;
Cps(ind1)=Cs(ind1);
 
% Speed of sound
u=1./sqrt(betaTs.*rhos-alphaPs.^2.*T./Cps);