Ernst Werner Hans Zocher, German/Brazilian physical chemist (Bad Liebenstein, Thüringen 27 April 1893 – Rio de Janeiro 16 October 1969)

ACHIEVEMENTS

Authored over 80 works

First to recognize a lyotropic nematic phase known as Zocher phase (1925)

Observed that colloidal particles sometimes aggregate in bundles which named tactoids (1925)

Presented equations for an orthotropic linear viscoelastic material

With Oseen introduced the macroscopic thermodynamical description of the liquid crystals

With Jacobsohn described a new type of sol called tactosol (1929)

Discovered inorganic lyotropic liquid crystals (1920s)

First to observe cholesteric-nematic phase transition effect (1929)

With Clara Torok first introduced tactoid shape characterization

Introduced term mesophase

Introduced an apparatus for examining shape of particles in colloidal solutions

With F. Stiebel introduced an ultramicroscopic technique for the study of monolayers by which they established the existence of inhomogeneities in extremely thin surface layers (1930)  

Described an electrode cleaning method (with Birstein)

With P. Kubelka and C. Torok developed and patented a method for extraction of potassium salts from saltwater employing its precipitation as syngenite (1959)

EPONYMY

Zocher effect

Zocher layers

Zocher number

Zocher rule “the linear dichroism of a colloidal dispersion reaches a maximum when its linear birefringence is zero” (1925)

Zocher type particles

Oseen-Zocher-Frank equations

Oseen-Zocher-Frank elastic constants

Oseen-Zocher-Frank free energy density

Zocher ferric oxide iridescent films

Zocher-Jacobsohn method (1928)

Zocher method for preparing sols