14:56 Sun 19 May 2 of 8 SECTION A qmplus.qmul.ac.uk Answer ALL questions in Section A Expect to use about half a page for each section A solution. Question A1 Give the term used in condensed matter physics for each of the following: a) The centre of the Brillouin zone [1 mark] b) A method for generating a neutron beam by bombarding a heavy metal target with protons [1 mark] c) The group of atoms associated with each lattice point in a crystal structure d) The Fourier transform of the lattice of a crystal [1 mark] [1 mark] e) A vibrational mode whose frequency tends to zero as the wavevector approaches zero [1 mark] f) A model of electronic structure in which electrons move in a weak, periodic potential and do not interact with each other by the Coulomb force [1 mark] Question A2 The body-centred cubic structure is common among metals. a) How many nearest neighbours has each atom in this structure? Give the nearest-neighbour distance in terms of the unit cell parameter a. [2 marks] b) How many second-nearest neighbours has each atom in this structure? Give the second- nearest-neighbour distance in terms of the unit cell parameter a. [2 marks] @ 96%

14:56 Sun 19 May 2 of 8 SECTION A qmplus.qmul.ac.uk Answer ALL questions in Section A Expect to use about half a page for each section A solution. Question A1 Give the term used in condensed matter physics for each of the following: a) The centre of the Brillouin zone [1 mark] b) A method for generating a neutron beam by bombarding a heavy metal target with protons [1 mark] c) The group of atoms associated with each lattice point in a crystal structure d) The Fourier transform of the lattice of a crystal [1 mark] [1 mark] e) A vibrational mode whose frequency tends to zero as the wavevector approaches zero [1 mark] f) A model of electronic structure in which electrons move in a weak, periodic potential and do not interact with each other by the Coulomb force [1 mark] Question A2 The body-centred cubic structure is common among metals. a) How many nearest neighbours has each atom in this structure? Give the nearest-neighbour distance in terms of the unit cell parameter a. [2 marks] b) How many second-nearest neighbours has each atom in this structure? Give the second- nearest-neighbour distance in terms of the unit cell parameter a. [2 marks] @ 96%