| Reference number | Title | Date |
| PB/7/2/4/19 | Rutherford Centenary Celebrations, Moscow, August 1971 | 1971 |
| HWT/33/2 | H W Thompson's personal correspondence as Foreign Secretary | January - June 1966 |
| S/0030 | Sculpture bust of Kapitza, Piotr Leonidovich | |
| IM/002477 | Group photograph | 1973 |
| IM/002475 | Kapitza, Piotr Leonidovich | nd |
| EC/1929/09 | Kapitza, Piotr Leonidovich: certificate of election to the Royal Society | 2 May 1929 |
| RR/48/58 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'The theory of alloys in the Y-phase' by Harry Jones | [November 1933] |
| RR/50/9 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'The supraconductivity of alloy systems' by J F Allen | April 1933 |
| RR/42/10 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'On the change of resistance of nickel in a magnetic field' by H H Potter | May 1931 |
| NLB/73/211 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to the Manager, Equitable Life Assurance Society, 19 Coleman Street, EC2 | 3 March 1931 |
| RR/42/72 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'The magnetic susceptibility of binary systems of organic liquids' by V C G Trew and James F Spencer | January 1931 |
| RR/44/14 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'The diamagnetic susceptibilities of some beryllium compounds' by William Rogie Angus and James Farquharson | February 1932 |
| RR/44/15 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'Ionic diamagnetic susceptibilities' by William Rogie Angus | February 1932 |
| RR/46/19 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'Investigations of magne-crystallic action. Part II.-Paramagnetics' by Kariamanikkam Srinivasa Krishnan, N C Chakravorty and S Banerjee | [January 1933] |
| NLB/73/393 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to the Assistant Actuary, London Life Association Ltd, 81 King William Street, EC4 | 16 September 1931 |
| RR/53/146 | Referee's report by John Cunningham McLennan, on a paper 'The liquefaction of helium by an adiabatic method' by Piotr Leonidovich Kapitza | [September 1934] |
| RR/65/148 | Referee's report by John Douglas Cockcroft, on a paper 'The Zeeman and Paschen-back effects in strong magnetic mields' by Piotr Leonidovich Kapitza, P G Strelkov and E Laurman | February 1938 |
| RR/65/149 | Referee's report by Edmund Clifton Stoner, on a paper 'The Zeeman and Paschen-back effects in strong magnetic mields' by Piotr Leonidovich Kapitza, P G Strelkov and E Laurman | March 1938 |
| NLB/73/206 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Prof. [Piotr] Kapitza, FRS | 27 February 1931 |
| NLB/73/114 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to the Assistant Treasurer, University Offices, St. Andrew's Street, Cambridge | 12 December 1930 |
| NLB/73/111 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to the Manager, Equitable Life Assurance Society, 19 Coleman Street, EC2 | 12 December 1930 |
| NLB/73/318 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Prof. [Piotr] Kapitza, FRS | 29 May 1931 |
| NLB/73/70 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to The Actuary, London Life Association, Ltd., 81 King William Street, EC4 | 18 November 1930 |
| IM/002478 | Kapitza, Piotr Leonidovich | 2 February 1933 |
| RR/48/45 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'The principal magnetic susceptibilities of some paramagnetic crystals at low temperatures' by L C Jackson | [February 1933] |
| IM/002476 | Kapitza, Piotr Leonidovich | 4 May 1966 |
| RR/46/15 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'Investigations on magne-crystallic action. Part I.-Diamagnetics' by Kariamanikkam Srinivasa Krishnan, B C Guha and S Banerjee | [April 1932] |
| RR/48/120 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'The phenomena of superconductivity with alternating currents of high frequency' by John Cunningham McLennan, A C Burton, A Pitt and J O Wilhelm | [February 1932] |
| RR/50/93 | Referee's report by Piotr Leonidovich Kapitza, on a paper 'A simple method of demonstrating the paramagnetism and diamagnetism of substances in magnetic fields of low intensity' by Alexander Oliver Rankine | January 1934 |