Kossel born 1888 Berlin son of Nobel biochemist Albrecht Kossel. Kossel earned PhD Heidelberg 1911 under Philipp Lenard. Kossel assisted Sommerfeld Munich 1913 worked Bohr-Sommerfeld atomic model. Kossel proposed ionic bond octet rule theory 1916 independently of Lewis. Kossel first explained X-ray spectra absorption limits 1914-1920. Kossel co-developed Sommerfeld-Kossel displacement law 1919 linking neutral Z and ionized Z+1 spectra. Kossel explained X-ray absorption edge structure from electrons kicked to higher levels. Kossel proposed kinetic crystal growth theory 1928 Kossel-Stranski model. Kossel discovered X-ray lattice interference spherical waves in copper crystals 1934. Kossel signed professors vow allegiance Adolf Hitler 1933. Kossel professor Kiel 1921-1932 Danzig 1932-1945 Tübingen 1945-1953. Kossel awarded Max Planck Medal 1944. Kossel died 1956 Tübingen age 68.