International
Tables for
Crystallography
Volume C
Mathematical, physical and chemical tables
Edited by E. Prince

© International Union of Crystallography 2006
International Tables for Crystallography (2006). Vol. C. ch. 3.2, p. 157

Table 3.2.2.1 

F. M. Richardsa

Table 3.2.2.1 | top | pdf |
Possible substances for use as gradient-column components

Hydrophobic components Hydrophilic components
Liquid Approximate density at 298 K (g ml−1) α Solute Approximate maximum density of concentrated aqueous solution at 298 K (g ml−1)
Isooctane (2-methylheptane) 0.69 −0.8 Sodium chloride 1.20
Kerosene 0.79 −0.5 −0.8 Potassium chloride 1.40
m-Xylene 0.86 −0.85 Potassium iodide 1.63
Chlorobenzene 1.10 −1.1 Iron(III) sulfate 1.80
Bromobenzene 1.49 −1.3 Zinc bromide 2.00
Carbon tetrachloride 1.60 −1.9 Zinc iodide 2.39
Methyl iodide 2.28 −2.7 Thallium(I) formate 3.5
Bromoform 2.89 −0.9 Thallium(I) formate–malonate 4.3
s-Tetrabromoethane 2.96 −2.2    
Methylene iodide 3.32 −2.6 Ficoll† (60% w/w in water) 1.25

The density at temperature T K can be computed by substituting the values of the density at 298 K and α in the formula dT = d298 + 10−3α(T − 298).
†Trade name for a synthetic high-molecular-weight polysaccharide derivative.