Research output: Contribution to journal › Review article › peer-review
Borates—crystal structures of prospective nonlinear optical materials : High anisotropy of the thermal expansion caused by anharmonic atomic vibrations. / Bubnova, Rimma; Volkov, Sergey; Albert, Barbara; Filatov, Stanislav.
In: Crystals, Vol. 7, No. 3, 93, 22.03.2017.Research output: Contribution to journal › Review article › peer-review
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TY - JOUR
T1 - Borates—crystal structures of prospective nonlinear optical materials
T2 - High anisotropy of the thermal expansion caused by anharmonic atomic vibrations
AU - Bubnova, Rimma
AU - Volkov, Sergey
AU - Albert, Barbara
AU - Filatov, Stanislav
PY - 2017/3/22
Y1 - 2017/3/22
N2 - In the present study the thermal structure evolution is reviewed for known nonlinear optical borates such as β-BaB2O4, LiB3O5, CsLiB6O10, Li2B4O7, K2Al2B2O7, and α-BiB3O6, based on single-crystal and powder X-ray diffraction data collected over wide temperature ranges. Temperature-dependent measurements of further borates are presented for the first time: α-BaB2O4 (295-673 K), β-BaB2O4 (98-693 K), LiB3O5 (98-650 K) and K2Al2B2O7 (98-348 K). In addition to the established criteria for nonlinear optical (NLO) properties of crystals, here the role of the anisotropy and anharmonicity of the thermal vibrations of atoms is analysed as well as changes in their coordination spheres and the anisotropy of the thermal expansion of the crystal structure. Non-centrosymmetric borates, especially those that have NLO properties, often show distinct anisotropies for each cation in comparison to centrosymmetric borates. All considered NLO borates contain BO3 triangles, which are the principal cause of the strong anisotropy of the thermal expansion.
AB - In the present study the thermal structure evolution is reviewed for known nonlinear optical borates such as β-BaB2O4, LiB3O5, CsLiB6O10, Li2B4O7, K2Al2B2O7, and α-BiB3O6, based on single-crystal and powder X-ray diffraction data collected over wide temperature ranges. Temperature-dependent measurements of further borates are presented for the first time: α-BaB2O4 (295-673 K), β-BaB2O4 (98-693 K), LiB3O5 (98-650 K) and K2Al2B2O7 (98-348 K). In addition to the established criteria for nonlinear optical (NLO) properties of crystals, here the role of the anisotropy and anharmonicity of the thermal vibrations of atoms is analysed as well as changes in their coordination spheres and the anisotropy of the thermal expansion of the crystal structure. Non-centrosymmetric borates, especially those that have NLO properties, often show distinct anisotropies for each cation in comparison to centrosymmetric borates. All considered NLO borates contain BO3 triangles, which are the principal cause of the strong anisotropy of the thermal expansion.
KW - Anisotropic and anharmonic atomic vibrations
KW - Crystal structures at low and high temperatures
KW - Low- and high-temperature single-crystal and powder x-ray diffraction
KW - NLO borates
KW - Rigid boron-oxygen groups
KW - Thermal expansion
UR - http://www.scopus.com/inward/record.url?scp=85016112349&partnerID=8YFLogxK
U2 - 10.3390/cryst7030093
DO - 10.3390/cryst7030093
M3 - Review article
AN - SCOPUS:85016112349
VL - 7
JO - Liquid Crystals
JF - Liquid Crystals
SN - 0267-8292
IS - 3
M1 - 93
ER -
ID: 9460676