Dmitri Igorevich Diakonov, an outstanding theoretical physicist, passed away on 26 December 2012 after a heart attack. Most of his scientific life he worked at the Leningrad (later Petersburg) Nuclear Physics Institute. He started there in 1972 as a Ph.D. student and became a Deputy Head of the Theoretical Physics Department since 2005 when he returned after 8 years of working as a Full Professor in NORDITA (Copenhagen). He also spent extended periods of time as a visiting Professor in a number of research institutions over the world, including Ruhr-Universität-Bochum (Germany), RIKEN (Japan), Pennsylvania State University and Thomas Jefferson National Laboratory (USA), and Inha University (South Korea).

Dmitri Diakonov has made a large number of groundbreaking contributions to the physics. Already his early works on quantum hard processes in quantum chromodynamics (jointly with Y. Dokshitzer and S. Troian) brought him a worldwide recognition. Few years later D. Diakonov initiated a research program on non-perturbative phenomena in quantum chromodynamics. In a series of papers he has built up (in collaboration with Yu. Petrov and others) a theoretical framework starting from the theory of instanton vacuum through the theory of quarks (spontaneous breaking of chiral symmetry and dynamical mass generation) to the chiral theory of hadrons explaining main physical properties of barions and mesons. This theoretical picture has been confirmed both by experiments as well as numerical simulations and had a great impact on research in this field.

The prediction of exotic barions ("pentaquark") in 1997 by Diakonov (jointly with V. Petrov and M. Polyakov) attracted a great attention of the community and triggered an extraordinary experimental activity. The results still remain controversial, and the experimental and theoretical work continues.

Scientific interests of Dmitri Diakonov were very broad. Over recent years he worked, in particular, on the theory of confinement in QCD, theory of baryon asymmetry of the Universe in the standard model, theory of Bose condensation, properties of QCD at non-zero temperature and chemical potential. Only during the last two years he proposed a self-consistent model of quantum gravity, developed a theory describing properties of all baryonic resonances up to 2 GeV, and obtained important results on the low-x physics at the LHC. Pioneering works of Dmitri Diakonov have been recognized with numerous prestigious prizes, including the Alexander von Humboldt Award for "outstanding achievements in the field of theoretical physics" and the Mercator Professorship (Germany), the Award by Danish Royal Academy of Sciences and Carlsberg Foundation, and the Award by Japan Society for Promotion of Science. In 2011, he was elected a member of Academia Europaea.

Dmitri Diakonov was a dedicated lecturer at Academic University in St. Petersburg as well as at numerous universities and schools over the world, and a highly devoted mentor to a large number of students and young scientists. He was investing a lot of time and energy to promoting scientific research in Russia. Mitya was not only a great scientist but also a truly friendly and charming personality. His sudden death was really a shock for his numerous friends and colleagues...

Dmitri Diakonov authored more than 150 scientific papers. We list below some of his most important articles representing different directions of his research (chronologically ordered, with citation indices according to INSPIRE as of January 2013).

1. Hard Semiinclusive Processes in QCD. Yuri L. Dokshitzer, Dmitri Diakonov, S.I. Troian (St. Petersburg, INP). May 1978. 11 pp.
Published in Phys.Lett. B78 (1978) 290
DOI: 10.1016/0370-2693(78)90025-4
Cited by 191 records

2. On the Transverse Momentum Distribution of Massive Lepton Pairs. Yuri L. Dokshitzer, Dmitri Diakonov, S.I. Troian (St. Petersburg, INP). 1978. Published in Phys.Lett. B79 (1978) 269-272
DOI: 10.1016/0370-2693(78)90240-X
Cited by 170 records

3. Hard Processes in Quantum Chromodynamics. Yuri L. Dokshitzer, Dmitri Diakonov, S.I. Troian (St. Petersburg, INP). 1978. 127 pp. Published in Phys.Rept. 58 (1980) 269-395
DOI: 10.1016/0370-1573(80)90043-5
Cited by 720 records

4. Instanton Based Vacuum from Feynman Variational Principle. Dmitri Diakonov, V.Yu. Petrov (St. Petersburg, INP). Oct 1983. 41 pp. Published in Nucl.Phys. B245 (1984) 259
DOI: 10.1016/0550-3213(84)90432-2
Cited by 538 records

5. A Theory of Light Quarks in the Instanton Vacuum. Dmitri Diakonov, V.Yu. Petrov (St. Petersburg, INP). Apr 1985. 52 pp. Published in Nucl.Phys. B272 (1986) 457
DOI: 10.1016/0550-3213(86)90011-8
Cited by 601 records

6. A Chiral Theory of Nucleons. Dmitri Diakonov, V.Yu. Petrov, P.V. Pobylitsa (St. Petersburg, INP). Jun 1987. 60 pp. Published in Nucl.Phys. B306 (1988) 809
DOI: 10.1016/0550-3213(88)90443-9
Cited by 326 records

7. Nucleon parton distributions at low normalization point in the large N(c) limit. Dmitri Diakonov, V. Petrov, P. Pobylitsa, Maxim V. Polyakov (St. Petersburg, INP), C. Weiss (Ruhr U., Bochum). Jun 1996. 42 pp. Published in Nucl.Phys. B480 (1996) 341-380
DOI: 10.1016/S0550-3213(96)00486-5
e-Print: hep-ph/9606314
Cited by 205 records

8. Exotic anti-decuplet of baryons: Prediction from chiral solitons. Dmitri Diakonov (St. Petersburg, INP & Nordita), Victor Petrov (St. Petersburg, INP), Maxim V. Polyakov (St. Petersburg, INP & Ruhr U., Bochum). Mar 1997. 19 pp. Published in Z.Phys. A359 (1997) 305-314
DOI: 10.1007/s002180050406
e-Print: hep-ph/9703373
Cited by 757 records

9. Unpolarized and polarized quark distributions in the large N(c) limit. Dmitri Diakonov (Nordita), V.Yu. Petrov (St. Petersburg, INP), P.V. Pobylitsa, Maxim V. Polyakov (St. Petersburg, INP & Ruhr U., Bochum), C. Weiss (Ruhr U., Bochum). Mar 1997. 32 pp. Published in Phys.Rev. D56 (1997) 4069-4083
DOI: 10.1103/PhysRevD.56.4069
e-Print: hep-ph/9703420
Cited by 170 records

10. Light quarks in the instanton vacuum at finite baryon density. G.W. Carter (Bohr Inst.), Dmitri Diakonov (Nordita). Dec 1998. 29 pp. Published in Phys.Rev. D60 (1999) 016004
DOI: 10.1103/PhysRevD.60.016004
e-Print: hep-ph/9812445
Cited by 142 records

11. The Nonperturbative color Meissner effect in a two flavor color superconductor. G.W. Carter (SUNY, Stony Brook), Dmitri Diakonov (Nordita). Jan 2000. 27 pp. Published in Nucl.Phys. B582 (2000) 571-590
DOI: 10.1016/S0550-3213(00)00309-6
e-Print: hep-ph/0001318
Cited by 34 records

12. Loop structure of the lowest Bloch band for a Bose-Einstein condensate Diakonov, D; Jensen, LM; Pethick, CJ; et al. Source: PHYSICAL REVIEW A Volume: 66 Issue: 1 Article Number: 013604
DOI: 10.1103/PhysRevA.66.013604 Published: JUL 2002
Cited 60 times (Web of Science)

13. Instantons at work. Dmitri Diakonov (Nordita & St. Petersburg, INP). Dec 2002. 36 pp. Published in Prog.Part.Nucl.Phys. 51 (2003) 173-222
DOI: 10.1016/S0146-6410(03)90014-7
e-Print: hep-ph/0212026
Cited by 208 records

15. Quantum weights of dyons and of instantons with nontrivial holonomy. Dmitri Diakonov (Nordita & St. Petersburg, INP), Nikolay Gromov (St. Petersburg State U.), Victor Petrov (St. Petersburg, INP), Sergey Slizovskiy (St. Petersburg State U.). Apr 2004. 35 pp.
Published in Phys.Rev. D70 (2004) 036003
DOI: 10.1103/PhysRevD.70.036003
e-Print: hep-th/0404042
Cited by 76 records

16. Confining ensemble of dyons. Dmitri Diakonov, Victor Petrov (St. Petersburg, INP). Apr 2007. 25 pp. Published in Phys.Rev. D76 (2007) 056001
DOI: 10.1103/PhysRevD.76.056001
e-Print: arXiv:0704.3181 [hep-th]
Cited by 41 records

17. Towards lattice-regularized Quantum Gravity. Dmitri Diakonov (St. Petersburg, INP). Sep 2011. 20 pp. e-Print: arXiv:1109.0091 [hep-th]
Cited by 11 records