Hydrogen bonds in lithium niobate crystals of different composition
N.V. Sidorov, N.A. Teplyakova, M.N. Palatnikov
Tananaev Institute of Chemistry Subdivision of the Federal Research Centre «Kola Science Centre of the Russian Academy of Sciences»
DOI: 10.26456/pcascnn/2021.13.376
Original article
Abstract: An analysis of complex defects was carried out by IR-spectroscopy method in the area of OH– groups stretching vibrations. The defects are caused by hydrogen bonds present in the structure of nominally pure congruent lithium niobate crystals, crystals of stoichiometric composition with a different Li /Nb ratio, as well as in LiNbO3:Zn(0,04–6,5 мол.% ZnO) crystals doped in a wide range of concentrations due to direct doping of the melt method. Dopants were determined to influence OH– groups concentration, type and localization of complex defects in the crystals structure. A change in the amount of hydrogen sites in the LiNbO3 crystals structure was shown to evaluate the composition either stoichiometric or congruent. The character of OH– groups complexing with cation sublattice point defects was shown to change when doped crystals LiNbO3:Zn(0,04–6,5 мол.% ZnO) trespass concentration thresholds. Dopant incorporation mechanism changes at this drastically, thus crystal properties also change quite sharply. Frequencies (as well as quasi-elastic constants of OH– bonds) change in congruent and doped crystals due to a difference in electronegativities and ionic radii of the main and dopant cations.
Keywords: single crystal, lithium niobate, defects, IR absorption spectra, doping, stretching vibrations of OH– group
- Nikolay V. Sidorov – Dr. Sc., Professor, Chief Researcher and acting Head of Sector of Vibrational Spectroscopy of Materials of Electronic Engineering Laboratory, Tananaev Institute of Chemistry Subdivision of the Federal Research Centre «Kola Science Centre of the Russian Academy of Sciences»
- Natalya A. Teplyakova – Ph. D., Senior Researcher, Sector of Vibrational Spectroscopy of Materials of Electronic Engineering Laboratory, Tananaev Institute of Chemistry Subdivision of the Federal Research Centre «Kola Science Centre of the Russian Academy of Sciences»
- Mikhail N. Palatnikov – Dr. Sc., Chief Researcher and acting Head of Materials of Electronic Engineering Laboratory, Tananaev Institute of Chemistry Subdivision of the Federal Research Centre «Kola Science Centre of the Russian Academy of Sciences»
Reference:
Sidorov, N.V. Hydrogen bonds in lithium niobate crystals of different composition / N.V. Sidorov, N.A. Teplyakova, M.N. Palatnikov // Physical and chemical aspects of the study of clusters, nanostructures and nanomaterials. — 2021. — I. 13. — P. 376-382. DOI: 10.26456/pcascnn/2021.13.376. (In Russian).
Full article (in Russian): download PDF file
References:
1. Lеngyel K., Péter Á., Kovács L. et al. Growth, defect structure, and THz application of stoichiometric lithium niobate, Applied Physics Reviews, 2015, vol. 2, issue 4, pp. 040601-1-040601-28. DOI: 10.1063/1.4929917.
2. Arizmendi L., Ambite E.J., Plaza J.L. Analysis of the OH– binding energy in lithium niobate crystals, Optical Materials, 2013, vol. 35, issue 12, pp. 2411-2413. DOI: 10.1016/j.opt.mat.2013.06.043.
3. Gała̧ zka Z. Radial temperature distribution in LiNbO3 crystals pulled by the Czochralski technigue, Journal of Crystal Growth, 1997, vol. 178, issue 3, pp. 345-349. DOI: 10.1016/S0022-0248(96)01159-1.
4. Lengyel K., Kovács L., Péter A. et al. // Thermal kinetics of OH– ions in LiNbO3:Mg crystals above the photorefractive threshold, Applied Physics Letters, 2010, vol. 96, issue 19, pp. 191907-1-191907-3. DOI: 10.1063/1.3428772.
5. Polgár K., Péter A., Kovács L., Corradi G., Szaller Zs. Growth of stoichiometric LiNbO3 single crystals by top seeded solution growth method, Journal of Crystal Growth, 1997, vol. 177, issue I. 3-4, pp. 211-216. DOI: 10.1016/S0022-0248(96)01098-6.
6. Volk T., Wohlecke M. Lithium niobate. Defects, photorefraction and ferroelectric switching. Berlin, Springer, 2008, 250 p. DOI: 10.1007/978-3-540-70766-0.
7. Palatnikov M.N., Sidorov N.V., Makarova O.V., Biryukova I.V. Fundamental'nye aspekty tekhnologii sil'no legirovannykh kristallov niobata litiya [Fundamental aspects of the technology of heavily doped lithium niobate crystals]. Apatity, KSC RAS Publ., 2017, 241 p. (In Russian).
8. Sidorov N.V., Volk T.P., Mavrin B.N., Kalinnikov V.T. Niobat litiya: defekty, fotorefraktsiya, kolebatel'nyi spektr, polyaritony [Lithium niobate: defects, photorefraction, vibrational spectrum, polaritons]. Moscow, Nauka Publ., 2003, 255 p. (In Russian).
9. Cabrera J.M., Olivares J., Carrascosa M. et al. Hydrogen in lithium niobate, Advances in Physics, 1996, vol. 45, issue 5, pp. 349-392. DOI: 10.1080/00018739600101517.
10. Liu J., Zhang W., Zhang G. Defect chemistry analysis of the defect structure in Mg -doped LiNbO3 crystals, Physica Status Solidi a, 1996, vol. 156, issue 2, pp. 285-291. DOI: 10.1002/pssa.2211560207.