September 1911, Bohr, supported by a fellowship from the Carlsberg Foundation, travelled to England. At the time, it was where most of the theoretical work on the structure of atoms and molecules was being done.[21] He met J. J. Thomson of the Cavendish Laboratory and Trinity College, Cambridge. He attended lectures on electromagnetism given by James Jeans and Joseph Larmor, and did some research on cathode rays, but failed to impress Thomson.[22][23] He had more success with younger physicists like the Australian William Lawrence Bragg,[24] and New Zealand's Ernest Rutherford, whose 1911 Rutherford model of the atom had challenged Thomson's 1904 plum pudding model.[25] Bohr received an invitation from Rutherford to conduct post-doctoral work at Victoria University of Manchester,[26] where Bohr met George de Hevesy and Charles Galton Darwin (whom Bohr referred to as "the grandson of the real Darwin").[27]
Bohr returned to Denmark in July 1912 for his wedding, and travelled around England and Scotland on his honeymoon. On his return, he became a privatdocent at the University of Copenhagen, giving lectures on thermodynamics. Martin Knudsen put Bohr's name forward for a docent, which was approved in July 1913, and Bohr then began teaching medical students.[28] His three papers, which later became famous as "the trilogy",[26] were published in Philosophical Magazine in July, September and November of that year.[29][30][31][32] He adapted Rutherford's nuclear structure to Max Planck's quantum theory and so created his Bohr model of the atom.[30]
Planetary models of atoms were not new, but Bohr's treatment was.[33] Taking the 1912 paper by Darwin on the role of electrons in the interaction of alpha particles with a nucleus as his starting point,[34][35] he advanced the theory of electrons travelling in orbits around the atom's nucleus, with the chemical properties of each element being largely determined by the number of electrons in the outer orbits of its atoms.[36] He introduced the idea that an electron could drop from a higher-energy orbit to a lower one, in the process emitting a quantum of discrete energy. This became a basis for what is now known as the old quantum theory.[37]