He worked on the chemistry of the lanthanides , and in 1902 proposed that an element was missing between neodymium and samarium ; it was later found to be promethium .
Brauner became lecturer for chemistry at the University of Prague in 1883 and professor in 1890 .
Brauner worked on the chemistry of the lanthanides , and in 1902 proposed that an element was missing between neodymium and samarium ; it was later found to be promethium .
Brauner became lecturer for chemistry at the University of Prague in 1883 and professor in 1890 .