MAIN FIELDS OF ACTIVITY AND INTEREST DURING THE LAST YEARS

Single molecule detection and spectroscopy




High-resolution spectroscopy of triplet carbenes - the hole burning study




Electronic excitation energy transfer and thermally activated fluorescence (TADF)in molecular crystals of charge-transfer complexes. Read an article here

PROJECTS

2018-2021. QuantERA call 2017: "Towards Room Temperature Quantum Technologies" (NCN 2017/25/Z/ST03038)
"W kierunku kwantowychtechnologii w temperaturze pokojowej"

2018-2021. QuantERA call 2017: Organic Quantum Integrated Devices (NCBiR)
"Organiczne Kwantowe Zintegrowane Urzadzenia"

2016-2018. (2015/17/B/ST2/01744)
"Optically controlled single-molecule transistor" (Optycznie sterowany tranzystor jedno-molekularny)

2008-2011. (N N202 204034)
"Single molecules as probes of the structural changes of the nano-environment" (Pojedyncza czasteczka jako sonda zmian strukturalnych w jej nanootoczeniu)

2007-2009.(N202 051 32/1188)
"Changes of the matrix nanostructure with temperature monitored with the aid of fluorescent single molecule probes" (Temperaturowe zmiany nano-struktury matrycy krystalicznej rejestrowane za pomoca fluorescencyjnej sondy jedno-molekularnej)

2003-2006. (2 P03B 079 24)
"Crystall structure dynamics investigated with single molecule probes" (Dynamika sieci krystalicznej badana przy pomocy sondy jedno-molekularnej)

2001-2002. (7 T09A 052 20)
"Relaxation of electronically excited triplet states in carbenes" (Relaksacja elektronowo wzbudzonych stanów tripletowych w karbenach)

1997-2001. (2 P03B 046 12)
"Single molecules as probes of their nano-environment" (Pojedyncze cz¹steczki jako sondy ich nano-otoczenia)

1993-1996. (2 P302 075 04)
"Electronic energy transfer between charge-transfer states" (Przenoszenie elektronowej energii wzbudzenia pomiedzy stanami charge-transfer)

REPRESENTATIVE PUBLICATIONS

114. Reverse Intersystem Crossing of Single Deuterated Perylene Molecules in a Dibenzothiophene Matrix
Robert Smit, Zoran Ristanovic, Bolesław Kozankiewicz, Michel Orrit,
ChemPhysChem 23 (2022) e202100679.

113. High-resolution vibronic spectroscopy of a single molecule embedded in a crystal
Johannes Zirkelbach, Masoud Mirzaei,Irena Deperasińska, Bolesław Kozankiewicz,Burak Gurlek,Alexey Shkarin,Tobias Utikal, Stephan Gotzinger, Vahid Sandoghdar,
The Journal of Chemical Physics 154 (2022) 104301.

112. Single organic molecules for photonic quantum technologies.
C. Toninelli, I. Gerhardt, A.S. Clark, A. Reserbat-Plantey, S. Goetzinger, Z. Ristanovic, M. Colautti, P. Lombardi, K.D. Major, Irena Deperasińska, W.H. Pernice, F.H.L. Koppens, Bolesław Kozankiewicz, A. Gourdon, V. Sandoghdar, Michel Orrit,
Nature Materials 20 (2021) 1615-1628.

111. Potent strategy towards strongly emissive nitroaromatics through a weakly electron-deficient core.
Bartłomiej Sadowski, Marzena Kaliszewska, Yevgen M. Poronik, Małgorzata Czichy, Patryk Janasik, Marzena Banasiewicz, Dominik Mierzwa, Wojciech Gadomski, Trevor D. Lohrey, John A. Clark, Mieczysław Lapkowski, Bolesław Kozankiewicz, Valentine I. Vullev,* Andrzej L. Sobolewski, Piotr Piatkowski, Daniel T. Gryko,
Chemical Science 12 (2021) 14039-14049.

110. Spectra and nature of the electronic states of [1]Benzothieno[3,2?b][1]benzothiophene (BTBT): single crystal and the aggregates.
Irena Deperasińska, Marzena Banasiewicz, Paweł Gawrys, Olaf Morawski, Joanna Olas, Bolesław Kozankiewicz,
The Journal of Chemical Physics 155 (2021) 034504.

109. Synthesis and absorption properties of long acenoacenes.
Andrej Jancarik, Daniel Mildner, Yuuya Nagata, Marzena Banasiewicz, Joanna Olas, Bolesław Kozankiewicz, Jan Holec, and André Gourdon,
Chemistry - A European Journal 27 (2021) 12388-12394.

108. A large starphene comprising pentacene branches.
Jan Holec, Beatrice Cogliati, James Lawrence, Alejandro Berdonces-Layunta, Pablo Herrero, Yuuya Nagata, Marzena Banasiewicz, Bolesław Kozankiewicz, Martina Corso, Dimas G. de Oteyza, Andrej Jancarik*, Andre Gourdon*,
Angewandte Chemie International Edition 60 (2021) 7752-7758.

107. Substituent effects on the photophysical properties of tris(salicylideneanilines).
Cristina A. Barboza*, Paweł Gawrys, Marzena Banasiewicz, Bolesław Kozankiewicz, Andrzej Sobolewski,
Phys. Chem. Chem. Phys. 23 (2021) 1156-1164.

106. Laser-Induced Frequency Tuning of Fourier-Limited Single-Molecule Emitters.
Maja Colautti, Francesco S. Piccioli, Zoran Ristanoviæ, Pietro Lombardi, Amin Moradi, Subhasis Adhikari, Irena Deperasińska, Bolesław Kozankiewicz, Michel Orrit*, and Costanza Toninelli*
ACS Nano 14 (2020) 13584-13592.

105. Effect of the substituent position on the electrochemical, optical and structural properties of donor-acceptor type acridone derivatives
Irena Kulszewicz-Bajer, Malgorzata Zagorska, Marzena Banasiewicz, Piotr A. Guñka, Petr Toman, Bolesław Kozankiewicz, Gabriela Wiosna-Salyga and Adam Pron*
Phys. Chem. Chem. Phys. 22 (2020) 8522-8534.

104. Shape control over microwave hydrothermally grown Y₂O₃:Eu by europium concentration adjustment
Jaros³aw Kaszewski, Julita Rosowska, Bart³omiej S. Witkowski, £ukasz Wachnicki, Karolina Wenelska, Ewa Mijowska, Lev-Ivan Bulyk, Damian W³odarczyk, Andrzej Suchocki, Bolesław Kozankiewicz, Marek Godlewski
Journal of Rare Earths 37 (2019) ? 1206-1212.

103. Spectra and nature of the electronic states of 2,3-dibromonaphthalene single crystal
A. Irena Deperasińska, Marzena Banasiewicz, and Bolesław Kozankiewicz
Journal of Luminescence 213 (2019) 108-116.

102. Matrix-induced Linear Stark Effect of Single Dibenzoterrylene Molecules in 2,3-Dibromonaphthalene Crystal
A. Moradi, Z. Ristanovic, Michel Orrit, Irena Deperasińska, Bolesław Kozankiewicz
ChemPhysChem 20 (2019) 55-61.

101. Fluorescence of 4-(Diisopropyloamino)benzonitrile (DIABN) Single Crystals from 300 K down to 5 K. Intermolecular Charge Transfer Disappears below 60 K
K. A. Zachariasse, S. I. Druzhinin, Olaf Morawski, and Bolesław Kozankiewicz
J. Phys. Chem. A 112 (2018) 6985-6996.

100. Synthesis and Photophysical Properties of N-arylated Diketopyrrolopyrroles
O. K. Gutowski, C. Azarias, Marzena Banasiewicz, Bolesław Kozankiewicz, D. Jacquemin, Daniel T. Gryko
Europ. J. Org. Chem. (2018) 6643-6648.

99. Unprecedented rearrangement of/**/diketopyrrolopyrroles leads to structurally unique chromophores
O. Vakuliuk, S. Ooi, I. Deperasińska, O. Staszewska-Krajewska, Marzena Banasiewicz, Bolesław Kozankiewicz, O. Danylyuk and Daniel T. Gryko
Chemical Communications 53 (2017) 11877-11880.

98. Anomalous doping of a molecular crystal monitored with confocal fluorescence microscopy. Terrylene in a p-terphenyl crystal
Magda Białkowska, Irena Deperasińska, Artur Makarewicz, and Bolesław Kozankiewicz
The Journal of Chemical Physics 147 (2017) 114302.

97. Non-planar distortion of terrylene molecules in a naphthalene crystal
Irena Deperasińska, Bolesław Kozankiewicz
Chemical Physics Letters 684 (2017) 208-211.

96. Symmetry Breaking in Pyrrolo[3,2-b]pyrroles: Synthesis, Solvatofluorochromism and Two-photon Absorption
L.G. Lukasiewicz, H.G. Ryu, A. Mikhaylov, C. Azarias, Marzena Banasiewicz, Bolesław Kozankiewicz, K.H. Ahn, D. Jacquemin, A. Rebane, Daniel T. Gryko
Chemistry-An Asian Journal 12 (2017) 1736-1748.

95. New quinacridone derivatves with -extended conjugation in central core
P. Kurzep, L. Skorka, M. Zagórska, Marzena Banasiewicz, P. Guńka, Bolesław Kozankiewicz, I. Kulszewicz-Bajer
RSC Advances 7 (2017) 8627-8632.

94. Single molecules of terrylene in di-substituted naphthalenes crystallizing in the herringbone pattern
Magda Białkowska, W. Chaladaj, Irena Deperasińska, A. Drzewiecka-Antonik, A.E. Koziol, Artur Makarewicz, Bolesław Kozankiewicz
RSC Advances 7 (2017) 2780-2788.

93. Reduction of Tb⁴⁺ ions in luminescent Y₂O₃:Tb nanorods prepared by microwave hydrothermal route
J. Kaszewski, B.S. Witkowski, L. Wachnicki, H. Przybylinska, Bolesław Kozankiewicz, E. Mijowska, M. Godlewski
Journal of Rare Earths 34 (2016) 774-781.

92. Luminescence enhancement in nanocrystalline Eu₂O₃ nanorods - Microwave hydrothermal ceystallization and thermal degradation of cubic phase
J. Kaszewski, B.S. Witkowski, L. Wachnicki, H. Przybylinska, Bolesław Kozankiewicz, E. Mijowska, M. Godlewski
Optical Materials 59 (2016) 76-82.

91. Y₂O₃:Eu nanocrystals as biomarkers prepared by a microwave hydrothermal method
J. Kaszewski, M.M. Godlewski, B.S. Witkowski, A. Slonska, E. Wolska-Kornio, L. Wachnicki, H. Przybylinska, Bolesław Kozankiewicz, A. Szal, M.A. Domino, E. Mijowska, M. Godlewski,
Optical Materials 59 (2016) 157-164.

90. Unexpected formation of π-expanded isoquinoline from anthracene possessing four electron-donating groups via the Duff reaction
M.K. Weclawski, I. Deperasińska, A. Leniak, Marzena Banasiewicz, Bolesław Kozankiewicz, Daniel T. Gryko
Organic & Biomolecular Chemistry 14 (2016) 7046-7052.

89. Dipyrrolonaphthyridinediones - structurally unique cross-conjugated dyes
M. Grzybowski, Irena Deperasińska, M. Chotkowski, Marzena Banasiewicz, A. Makarewicz, Bolesław Kozankiewicz, Daniel T. Gryko
Chemical Communications 52 (2016) 5108-5111.

88. Dipolar Dyes with a Pyrrolo[2,3-b]quinoxaline Skeleton Containing a Cyano Group and a Bridged Tertiary Amino Group: Synthesis, Solvatofluorochromism and Bioimaging
L.G. Lukasiewicz, I. Deperasińska, Y.M. Poronik, Y. Woong Jun, Marzena Banasiewicz, Bolesław Kozankiewicz,K. Han Ahn, Daniel T. Gryko
Chemistry An Asian Journal 11 (2016) 1718-1724.

87. Solvatofluorochromic, non-centrosymmetric π-expanded diketopyrrolopyrrole
T. M. Grzybowski, A. Jezewski, Irena Deperasińska, D.H. Friese, M. Banasiewicz, V. Hugues, Bolesław Kozankiewicz, M. Blanchard-Desce, Daniel T. Gryko
Organic & Biomolecular Chemistry 14 (2016) 2025-2033.

86. Double head-to-tail direct arylation as a viable strategy towards the synthesis of the aza-analog of dihydrocyclopenta[hi]aceanthrylene - an intriguing antiaromatic heterocycle
D. Firmansyah, Irena Deperasińska, O. Vakuliuk, M. Banasiewicz, M. Tasior, A. Makarewicz, Michał K. Cyraśski, Bolesław Kozankiewicz, Daniel T. Gryko
Chemical Communication 52 (2016) 1262-1265.

85. Terrylene in a 2,3 dichloronaphthalene crystal. New system for optical single-molecule investigations
Magda Białkowska, W. Chaladaj, Artur Makarewicz and Bolesław Kozankiewicz
Acta Physica Polonica A 128 (2015) RK.128.3.1-1 - RK.128.3.1-4.

84. The environment-sensitive behavior of DCNP in solvents with different viscosity, polarity and proticity
Olaf Morawski, Bolesław Kozankiewicz, A. Miniewicz, Andrzej L. Sobolewski
ChemPhysChem 16 (2015) 3500-3510.

83. Why vertically π-expanded imidazo[1,2-a]pyridines are weak fluorescence emitters: experimental and computational study
Marzena Banasiewicz, Irena Deperasińska, Artur Makarewicz, D. Firmansyah, Daniel T. Gryko, Bolesław Kozankiewicz
Phys. Chem. Chem. Phys. 17 (2015) 8945-8950.

82. Photophysics of Derivatives of 3-Hydroxybenzo[c]coumarin
Irena Deperasińska, Artur Makarewicz, M. Krzeszewski, Daniel T. Gryko, Bolesław Kozankiewicz
J. Phys. Chem. A 119 (2015) 9051-9058.

81. On the origin of fluorescence in optically non-linear DCNP crystal
Olaf Morawski, Andrzej L. Sobolewski, Bolesław Kozankiewicz, L. Sznitko, A. Miniewicz
Phys. Chem. Chem. Phys. 16 (2014) 26887-26892.

80. Vertically π-Expanded Imidazo[1,2-a]pyridine – Missing Link of the Puzzle
D. Firmansyah, Marzena Banasiewicz, Irena Deperasińska, A. Makarewicz, Bolesław Kozankiewicz, D. T. Gryko
Chemistry - An Asian Journal 9 (2014) 2483-2493.

79. Vertically π-Expanded Coumarin – the Synthesis via the Scholl Reaction and Photophysical Properties
M. Tasior, Irena Deperasińska, K. Morawska, Marzena Banasiewicz, O. Vakuliuk, Bolesław Kozankiewicz, Daniel T. Gryko
Phys. Chem. Chem. Phys. 16 (2014) 18268-18275.

78. VSingle-molecule photophysics, from cryogenic to ambient conditions
Bolesław Kozankiewicz, Michel Orrit
Chemical Society Reviews. 43 (2014) 1029-1043.

77. Nanoscale probing of charge transport in an organic field-effect transistor at cryogenic temperatures
A.A.L. Nicolet, M.A. Kol'chenko, C. Hofmann, Bolesław Kozankiewicz, and Michel Orrit
Phys. Chem. Chem. Phys. 15 (2013) 4415-4421.

76. Spin-lattice relaxation and anomalous intersystem crossing in single molecule of terrylene embedded in p-perphenyl crystal
Magda Białkowska, Artur Makarewicz, Marzena Banasiewicz, Bolesław Kozankiewicz
Chem. Phys. Letters 555 (2013) 131-134.

75. Low Temperature Spectra of the Analogues of 10-Hydroxybenzo[h]quinoline as Indication of Barrierless ESIPT
Irena Deperasińska, Daniel T. Gryko, Elena Karpiuk, Bolesław Kozankiewicz, Artur Makarewicz, Joanna Piechowska
J. Phys. Chem. A 116 (2012) 12049-12055.

74. Spectral Diffusion of Single Dibenzoterrylene Molecules in 2,3-Dimethylanthracene
Y. Tian, P. Navarro, Bolesław Kozankiewicz, Michel Orrit
ChemPhysChem 13 (2012) 3510-3515.

73. Photochemical isomerizations of thiosemicarbazide: a matrix isolation study
Hanna Rostkowska, Leszek Lapinski, Bolesław Kozankiewicz, Maciej J. Nowak
J. Phys. Chem. A 116 (2012) 9863-9871.

72. Low temperature emission spectra of optically nonlinear N-benzyl-2-methyl-4-nitroaniline crystal
K. Piela, Bolesław Kozankiewicz, J. Lipinski, M. M. Szostak
Chemical Physics 404 (2012) 28-32.

71. Vibronic spectra of single dibenzoterrylene molecules in anthracene and 2,3-dimenthylanthracene crystals
Artur Makarewicz, Irena Deperasińska, Elena Karpiuk, Jacek Nowacki, Bolesław Kozankiewicz
Chem. Phys. Letter 535 (2012) 140-145.

70. 12-Hydroxy-1-Azaperylene - Limiting Case of the ESIPT System: Enol-Keto Tautomerization in S₀ and S₁ State
Irena Deperasińska, Daniel T. Gryko, Elena Karpiuk, Bolesław Kozankiewicz, Artur Makarewicz, Joanna Piechowska
J. Phys. Chem. A 116 (2012) 2109-2116.

69. On Photo-Oxidation of Single Molecules
Bolesław Kozankiewicz, Irena Deperasińska, Elena Karpiuk, Marzena Banasiewicz, Artur Makarewicz
Optical Materials 33 (2011) 1391.

68. Single dibenzoterrylene molecules in naphthalene and 2,3-dimethylnaphthalene crystals: vibronic spectra
Irena Deperasińska, Elena Karpiuk, Marzena Banasiewicz, Artur Makarewicz, Bolesław Kozankiewicz
Phys. Chem. Chem. Phys. 13 (2011) 1872.

67. On the photostability of single molecules. Dibenzoterrylene in 2,3-dimethylnaphthalene
Irena Deperasińska, Elena Karpiuk, Marzena Banasiewicz, Bolesław Kozankiewicz
Chem. Phys. Letters 492 (2010) 93.

66. Single molecules detect ultra-slow oscillators in a molecular crystal excited by ac-voltages
M.A. Kolchenko, A.A.L. Nicolet, M.D. Galouzis, C. Hofmann, Bolesław Kozankiewicz, Michel Orrit
New Journal of Physics 11 (2009) 023037.

65. Photo-stability of single terrylene molecules in 2,3-dimethylnaphthalene crystals
R. Kosciesza, Elena Luzina, Dariusz Wiącek, J. Dresner, Bolesław Kozankiewicz
Molecular Physics 107 (2009) 1889.

64. Nonplanar Distortion of Single Molecule Revealed by Vibronic Fluorescence Excitation: Terrylene in p-Terphenyl and Naphthalene Crystals
Dariusz Wiącek and Bolesław Kozankiewicz
Molecular Physics 462 (2008) 280.

63. Purely electronic and vibronic excitation of single terrylene molecules in a naphthalene crystal
Marzena Banasiewicz, J. Dresner, Olaf Morawski, Dariusz Wiącek, and Bolesław Kozankiewicz
Acta Physica Polonica A 112 (2007) S85.

62. Single dibenzoterrylene molecules in an anthracene crystal. Main insertion sites
Nicolet, P. Bordat, C. Hofmann, M.A. Kol'chenko, Bolesław Kozankiewicz, R. Brown and Michel Orrit
ChemPhysChem 8 (2007) 1926.

61. Single dibenzoterrylene molecules in an anthracene crystal. I. Spectroscopy and photophysics
A. Nicolet, C. Hofmann, M. Kol'chenko, Bolesław Kozankiewicz, and Michel Orrit
ChemPhysChem 8 (2007) 1215.

60. Low-temperature photoluminescence of p-nitroaniline and o-methyl-p-nitroaniline crystals
M.M. Szostak, Bolesław Kozankiewicz, and Jó Lipin
Spectrochimica Acta A 67 (2007) 1412.

59. Intermolecular intersystem-crossing in single-molecule spectroscopy: Terrylene in anthracene crystals
A. Nicolet, M. Kol'chenko, Bolesław Kozankiewicz, and Michel Orrit,
J. Chem. Phys. 124 (2006) 164711-7.

58. Structural dynamics of 2,3-dimethyl-naphthalene crystals revealed by fluorescence of single terrylene molecules
Marzena Banasiewicz, Dariusz Wiącek, and Bolesław Kozankiewicz
Chem. Phys. Letters 245 (2006) 94-98.

57. Photobleaching of single terrylene molecules in Shpol¿skii matrices at elevated temperatures
Marzena Banasiewicz, Dariusz Wiącek, and Bolesław Kozankiewicz
Chem. Phys. Letters 245 (2006) 289-293.

56. Triplet Population and Depopulation Rates of Single Terrylene Molecules in p-Terphenyl Crystal
Marzena Banasiewicz, Olaf Morawski, Dariusz Wiącek, and Bolesław Kozankiewicz
Chem. Phys. Letters 414 (2005) 374-377.

55. Intersystem Crossing Mechanisms and Single Molecule Fluorescence. Terrylene in Anthracene Crystals
M.A. Kol'chenko, Bolesław Kozankiewicz, A. Nicolet, and Michel Orrit
Optics and Spectroscopy 98 (2005) 681-686.

54. Spectroscopic Characteristics of Pentacene In Shpol'skii Matrixes
Marzena Banasiewicz, Irena Deperasińska, Bolesław Kozankiewicz
J. Phys. Chem. A 107 (2003) 662-667.

53. Excited singlet state relaxation yields of pentacene in Shpol'skii matrices
Marzena Banasiewicz, Irena Deperasińska, D. Fabjanowicz and Bolesław Kozankiewicz
Chem. Phys. Letters 356 (2002) 541-546.

52. Intersystem crossing of single pentacene molecules in Shpol'skii matrices
Bolesław Kozankiewicz, Marzena Banasiewicz, J. Dresner and Michel Orrit
Chem. Phys. Letters 343 (2001) 71-76.

51. Anomalous Fluorescence of Terrylene in Neon Matrix
Irena Deperasińska, Bolesław Kozankiewicz, I. Baktchantaev, J. Sepioł,
J. Phys. Chem. A 105 (2001) 810-814.

50. A hole burning study of the zero-field splitting of the triplet ground and excited states of 2,2-dinaphthylcarbene in n-heptane and n-hexane at 1.7 K
Bolesław Kozankiewicz, M. Aloshyna, Michel Orrit, P. Tamarat, A. D. Gudmundsdottir and M. S. Platz
J. Phys. Chem. A 104 (2000) 7464-7468.

49. Zero-field splitting of the triplet ground and excited states of 7h-benz[de]anthracen-7-ylidene in n-hexane at 1.7 K. A hole burning study
Bolesław Kozankiewicz, M. Aloshyna, A. Sienkiewicz, Michel Orrit, P. Tamarat, C. M. Hadad, J. R. Snoonian and M. S. Platz
J. Phys. Chem. A 104 (2000) 5213-5218.

48. Zero-field splitting of the electronic ground and lowest excited triplet states of 2,2-dinaphthylcarbene in n-hexane at 1.7 K
Bolesław Kozankiewicz, M. Aloshyna, A.D. Gudmundsdottir, M.S. Platz, Michel Orrit and Ph. Tamarat
J. Phys. Chem. A 103 (1999) 3155-3162.

47. Electronic energy transfer in the charge-transfer crystal of 2,3-Dimethylnaphthalene - Tetracyanobenzene
Bolesław Kozankiewicz
Journal of Luminescence 71 (1997) 37-46.

46. Singlet and triplet energy transfer in tetracyanobenzene - biphenyl crystals
Bolesław Kozankiewicz
Molecular Crystals and Liquid Crystals 293 (1997) 247-259.

45. Migration of electronic excitation energy in the charge-transfer crystal of pyromellitic dianhydride-phenanthrene
Bolesław Kozankiewicz, J. Al-Abbas and J. Prochorow
Chem. Phys. Letter 235 (1995) 456.

44. Migration of CT triplet excitons in TCNB-biphenyl and TCNB-HMB crystals
Bolesław Kozankiewicz
Chem. Phys. Letter 217 (1994) 91-96.

43. Single molecule lines and spectral hole-burning for terrylene in different matrices
Bolesław Kozankiewicz, J. Bernard and Michel Orrit
Journal of Chemical Physics 101 (1994) 9377.

SPECIAL ATTENTION IS REQUIRED FOR
Electronic excitation energy transfer and thermally activated fluorescence (TADF) in molecular crystals of charge-transfer complexes:

42. Kinetics of Delayed Emission in Charge-Transfer Crystals. TCPA-HMB Crystal.
Bolesław Kozankiewicz and Jerzy Prochorow
Mol. Cryst. Liq. Cryst. 148 (1987) 93-109. Read an article here