Font Alternates
The 
    font-variant-alternates CSS property controls the use of alternate
      glyphs, rather than the default ones.Warning: 
Currently, Oxygen PDF Chemistry
        supports only the 
styleset() function for
          font-variant-alternates.Style Sets
The styleset()
        function defines a stylistic alternative for sets of characters. The parameter is a
        font-specific name mapped to a number. It corresponds to the OpenType value
          ssXY (e.g. ss02). 
For example, if you have the
        following
        paragraph:
 <p>Lore ipsum dolor.</p>p {
  font-family: Gabriola;
  font-variant-alternates: styleset(ss06);
}
