logo

SCIENCE CHINA Materials, Volume 63 , Issue 9 : 1769-1778(2020) https://doi.org/10.1007/s40843-020-1310-1

Syntheses, characterization and calculations of LimAnM6O15 (A=Rb, Cs; M=Si, Ge; m+n=6)

More info
  • ReceivedFeb 19, 2020
  • AcceptedMar 19, 2020
  • PublishedMay 15, 2020

Abstract

Alike phosphates, silicates and germanates exclusively containing tetrahedral basic building units (BBUs) can also exhibit ultraviolet (UV) even deep-UV transitions. They are important for the design of new UV or deep-UV nonlinear optical (NLO) materials. In this paper, four new alkali metal silicates and germanates, Li2Rb4Si6O15, Li2Cs4Si6O15, Li3Rb3Ge6O15 and Li3Cs3Ge6O15 were successfully synthesized by a high temperature solid state reaction. They obey the general formula of LimAnM6O15 (A=Rb, Cs; M=Si, Ge; m+n=6) and all exhibit the Sr2Be2B2O7 (SBBO)-like structures. More importantly, Li3Rb3Ge6O15 and Li3Cs3Ge6O15 crystallize in the noncentrosymmetric (NCS) structures and exhibit remarkable phase-matched second harmonic generation (SHG) effect, 0.8×KH2PO4 (KDP) and 1×KDP, respectively. These indicate that they are potential as UV or deep-UV NLO materials. Furthermore, their optical and NLO properties as well as thermal properties were measured. The structure-property relationships were studied by the dipole moment calculations and the first-principles calculations.


Funded by

the Natural Science Foundation of Tianjin(19JCZDJC38200)

the National Natural Science Foundation of China(51802217,51972230,61835014,51890864,51890865)

and the National Key R&D Program of China(2016YFB0402103)


Acknowledgment

This work was supported by the Natural Science Foundation of Tianjin (19JCZDJC38200), the National Natural Science Foundation of China (51802217, 51972230, 61835014, 51890864 and 51890865), and the National Key R&D Program of China (2016YFB0402103).


Interest statement

The authors declare that they have no conflict of interest.


Contributions statement

Xu J performed the experiments, data analysis, and paper writing; Wu H, Yu H, Hu Z, Wang J and Wu Y designed the concept and supervised the experiments. All authors contributed to the general discussion.


Author information

Jingjing Xu received her BSc degree in applied physics from Tianjin University of Commerce in 2018. She is currently a master student in Professor Hongwei Yu’s research group at Tianjin University of Technology. Her research focuses on the syntheses, crystal growth, and evaluation of new optical electronic functional materials.


Hongwei Yu received his PhD degree in material physics and chemistry from the University of Chinese Academy of Sciences. He did post-doctoral research at Houston University and Northwestern University in USA from 2014 to 2017. From 2018, he has been working as a full professor at Tianjin University of Technology. His current research interests include the design, syntheses, crystal growth, and evaluation of new optical electronic functional materials.


Supplement

Supplementary information

The supporting data are available in the online version of the paper. Accession Codes: CCDC 1983008, 1983009, 1983010 and 1983011 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +441223 336033.


References

[1] Becker P. Borate materials in nonlinear optics. Adv Mater, 1998, 10: 979-992 CrossRef Google Scholar

[2] Halasyamani PS, Poeppelmeier KR. Noncentrosymmetric oxides. Chem Mater, 1998, 10: 2753-2769 CrossRef Google Scholar

[3] Wu H, Pan S, Poeppelmeier KR, et al. K3B6O10Cl: A new structure analogous to perovskite with a large second harmonic generation response and deep UV absorption edge. J Am Chem Soc, 2011, 133: 7786-7790 CrossRef PubMed Google Scholar

[4] Cyranoski D. Materials science: China’s crystal cache. Nature, 2009, 457: 953-955 CrossRef PubMed Google Scholar

[5] Tran TT, Yu H, Rondinelli JM, et al. Deep ultraviolet nonlinear optical materials. Chem Mater, 2016, 28: 5238-5258 CrossRef Google Scholar

[6] Zhang B, Shi G, Yang Z, et al. Fluorooxoborates: Beryllium-free deep-ultraviolet nonlinear optical materials without layered growth. Angew Chem Int Ed, 2017, 56: 3916-3919 CrossRef PubMed Google Scholar

[7] Wang Y, Zhang B, Yang Z, et al. Cation-tuned synthesis of fluorooxoborates: Towards optimal deep-ultraviolet nonlinear optical materials. Angew Chem Int Ed, 2018, 57: 2150-2154 CrossRef PubMed Google Scholar

[8] Wu H, Yu H, Yang Z, et al. Designing a deep-ultraviolet nonlinear optical material with a large second harmonic generation response. J Am Chem Soc, 2013, 135: 4215-4218 CrossRef PubMed Google Scholar

[9] Shen Y, Zhao S, Yang Y, et al. A new KBBF-family nonlinear optical material with strong interlayer bonding. Cryst Growth Des, 2017, 17: 4422-4427 CrossRef Google Scholar

[10] Zhou Z, Qiu Y, Liang F, et al. CsSiB3O7: A beryllium-free deep-ultraviolet nonlinear optical material discovered by the combination of electron diffraction and first-principles calculations. Chem Mater, 2018, 30: 2203-2207 CrossRef Google Scholar

[11] Miao Z, Yang Y, Wei Z, et al. A new barium-containing alkali metal silicate fluoride NaBa3Si2O7F with deep-UV optical property. Sci China Mater, 2019, 62: 1454-1462 CrossRef Google Scholar

[12] Yang Y, Gong P, Huang Q, et al. KNa4B2P3O13: A deep-ultraviolet transparent borophosphate exhibiting second-harmonic generation response. Inorg Chem, 2019, 58: 8918-8921 CrossRef PubMed Google Scholar

[13] Mutailipu M, Zhang M, Zhang B, et al. SrB5O7F3 functionalized with [B5O9F3]6− chromophores: Accelerating the rational design of deep-ultraviolet nonlinear optical materials. Angew Chem Int Ed, 2018, 57: 6095-6099 CrossRef PubMed Google Scholar

[14] Shi G, Wang Y, Zhang F, et al. Finding the next deep-ultraviolet nonlinear optical material: NH4B4O6F. J Am Chem Soc, 2017, 139: 10645-10648 CrossRef PubMed Google Scholar

[15] Chen X, Zhang B, Zhang F, et al. Designing an excellent deep-ultraviolet birefringent material for light polarization. J Am Chem Soc, 2018, 140: 16311-16319 CrossRef PubMed Google Scholar

[16] Chen CT, Wu BC, Jiang AD, et al. A new-type ultraviolet SHG crystal—β-BaB2O4. Sci Sin B, 1985, 28: 235−243. Google Scholar

[17] Chen C, Wu Y, Jiang A, et al. New nonlinear-optical crystal: LiB3O5. J Opt Soc Am B, 1989, 6: 616-621 CrossRef ADS Google Scholar

[18] Wu Y, Sasaki T, Nakai S, et al. CsB3O5: A new nonlinear optical crystal. Appl Phys Lett, 1993, 62: 2614-2615 CrossRef ADS Google Scholar

[19] Chen C, Wang Y, Xia Y, et al. New development of nonlinear optical crystals for the ultraviolet region with molecular engineering approach. J Appl Phys, 1995, 77: 2268-2272 CrossRef ADS Google Scholar

[20] Wang S, Ye N, Li W, et al. Alkaline beryllium borate NaBeB3O6 and ABe2B3O7 (A=K, Rb) as UV nonlinear optical crystals. J Am Chem Soc, 2010, 132: 8779-8786 CrossRef PubMed Google Scholar

[21] Wang S, Ye N. Na2CsBe6B5O15: An alkaline beryllium borate as a deep-UV nonlinear optical crystal. J Am Chem Soc, 2011, 133: 11458-11461 CrossRef PubMed Google Scholar

[22] Huang H, Liu L, Jin S, et al. Deep-ultraviolet nonlinear optical materials: Na2Be4B4O11 and LiNa5Be12B12O33. J Am Chem Soc, 2013, 135: 18319-18322 CrossRef PubMed Google Scholar

[23] Luo M, Liang F, Song Y, et al. M2B10O14F6 (M=Ca, Sr): Two noncentrosymmetric alkaline earth fluorooxoborates as promising next-generation deep-ultraviolet nonlinear optical materials. J Am Chem Soc, 2018, 140: 3884-3887 CrossRef PubMed Google Scholar

[24] Peng G, Ye N, Lin Z, et al. NH4Be2BO3F2 and γ-Be2BO3F: Overcoming the layering habit in KBe2BO3F2 for the next-generation deep-ultraviolet nonlinear optical materials. Angew Chem Int Ed, 2018, 57: 8968-8972 CrossRef PubMed Google Scholar

[25] Wang X, Wang Y, Zhang B, et al. CsB4O6F: A congruent-melting deep-ultraviolet nonlinear optical material by combining superior functional units. Angew Chem, 2017, 129: 14307-14311 CrossRef Google Scholar

[26] Yu H, Wu H, Pan S, et al. A novel deep UV nonlinear optical crystal Ba3B6O11F2, with a new fundamental building block, B6O14 group. J Mater Chem, 2012, 22: 9665 CrossRef Google Scholar

[27] Yang Z, Lei BH, Zhang W, et al. Module-analysis-assisted design of deep ultraviolet fluorooxoborates with extremely large gap and high structural stability. Chem Mater, 2019, 31: 2807-2813 CrossRef Google Scholar

[28] Chen C. Development of New Nonlinear Optical Crystals in The Borate Series. Reading: Harwood Academic Publishers, 1993. 74. Google Scholar

[29] Zhao S, Gong P, Luo S, et al. Tailored synthesis of a nonlinear optical phosphate with a short absorption edge. Angew Chem, 2015, 127: 4291-4295 CrossRef Google Scholar

[30] Zhao S, Gong P, Luo S, et al. Deep-ultraviolet transparent phosphates RbBa2(PO3)5 and Rb2Ba3(P2O7)2 show nonlinear optical activity from condensation of [PO4]3– units. J Am Chem Soc, 2014, 136: 8560-8563 CrossRef PubMed Google Scholar

[31] Zhao S, Yang X, Yang Y, et al. Non-centrosymmetricRbNaMgP2O7 with unprecedented thermo-induced enhancement of second harmonic generation. J Am Chem Soc, 2018, 140: 1592-1595 CrossRef PubMed Google Scholar

[32] Yu H, Young J, Wu H, et al. M4Mg4(P2O7)3(M=K, Rb): Structural engineering of pyrophosphates for nonlinear optical applications. Chem Mater, 2017, 29: 1845-1855 CrossRef Google Scholar

[33] Li L, Wang Y, Lei BH, et al. A new deep-ultraviolet transparent orthophosphate LiCs2PO4 with large second harmonic generation response. J Am Chem Soc, 2016, 138: 9101-9104 CrossRef PubMed Google Scholar

[34] Chen X, Zhang F, Liu L, et al. Li3AlSiO5: The first aluminosilicate as a potential deep-ultraviolet nonlinear optical crystal with the quaternary diamond-like structure. Phys Chem Chem Phys, 2016, 18: 4362-4369 CrossRef PubMed ADS Google Scholar

[35] Zhao B, Yang Y, Zhao S, et al. A new phase-matchable nonlinear optical silicate: Rb2ZnSi3O8. J Mater Chem C, 2017, 5: 11025-11029 CrossRef Google Scholar

[36] Zhao W, Zhang F, Liu J, et al. Flux crystal growth of Ba2TiOSi2O7. J Cryst Growth, 2015, 413: 46-50 CrossRef ADS Google Scholar

[37] Höche T, Neumann W, Esmaeilzadeh S, et al. The crystal structure of Sr2TiSi2O8. J Solid State Chem, 2002, 166: 15-23 CrossRef ADS Google Scholar

[38] Chao TL, Chang WJ, Wen SH, et al. Titanosilicates with strong phase-matched second harmonic generation responses. J Am Chem Soc, 2016, 138: 9061-9064 CrossRef PubMed Google Scholar

[39] Xia M, Tang C, Li R. Rb4Li2TiOGe4O12: A titanyl nonlinear optical material with the widest transparency range. Angew Chem Int Ed, 2019, 58: 18257-18260 CrossRef PubMed Google Scholar

[40] Xu J, Wu H, Yu H, et al. Li2K4TiOGe4O12: A stable mid-infrared nonlinear optical material. Chem Mater, 2020, 32: 906-912 CrossRef Google Scholar

[41] Becker P, Held P, Liebertz J, et al. Optical properties of the germanate melilites Sr2MgGe2O7, Sr2ZnGe2O7 and Ba2ZnGe2O7. Cryst Res Technol, 2009, 44: 603-612 CrossRef Google Scholar

[42] Kaminskii AA, Bohatý L, Becker P, et al. Tetragonal Ba2MgGe2O7-a novel multifunctional optical crystal with numerous manifestations of nonlinear-laser effects: Almost sesqui-octave Stokes and anti-Stokes combs and cascaded χ(3)χ(2) lasing with involved second and third harmonic generation. Laser Phys Lett, 2008, 5: 845-868 CrossRef ADS Google Scholar

[43] Jia Z, Jiang X, Lin Z, et al. PbTeGeO6: Polar rosiaite-type germanate featuring a two dimensional layered structure. Dalton Trans, 2018, 47: 16388-16392 CrossRef PubMed Google Scholar

[44] Tang RL, Hu CL, Wu BL, et al. Cs2Bi2O(Ge2O7) (CBGO): A larger SHG effect induced by synergistic polarizations of BiO5 polyhedra and GeO4 tetrahedra. Angew Chem Int Ed, 2019, 58: 15358-15361 CrossRef PubMed Google Scholar

[45] Bruker. Program SAINT. Madison: Bruker AXS Inc., 2012. Google Scholar

[46] Sheldrick GM. A short history of SHELX. Acta Crystallogr A, 2008, 64: 112. Google Scholar

[47] Kurtz SK, Perry TT. A powder technique for the evaluation of nonlinear optical materials. J Appl Phys, 1968, 39: 3798-3813 CrossRef ADS Google Scholar

[48] Clark SJ, Segall MD, Pickard CJ, et al. First principles methods using CASTEP. Z für Kristallographie-Crystline Mater, 2005, 220: 567–570. Google Scholar

[49] Perdew JP, Burke K, Ernzerhof M. Generalized gradient approximation made simple. Phys Rev Lett, 1996, 77: 3865-3868 CrossRef PubMed ADS Google Scholar

[50] Rappe AM, Rabe KM, Kaxiras E, et al. Optimized pseudopotentials. Phys Rev B, 1990, 41: 1227-1230 CrossRef PubMed ADS Google Scholar

[51] Lin JS, Qteish A, Payne MC, et al. Optimized and transferable nonlocal separable ab initio pseudopotentials. Phys Rev B, 1993, 47: 4174-4180 CrossRef PubMed ADS Google Scholar

[52] Tang RL, Hu CL, Mao FF, et al. Ba4Bi2(Si8−xB4+xO29) (x=0.09): A new acentric metal borosilicate as a promising nonlinear optical material. Chem Sci, 2019, 10: 837-842 CrossRef PubMed Google Scholar

[53] Wen M, Lian Z, Wu H, et al. Ba7(BO3)3GeO4X (X=Cl, Br): Borogermanate halides with rigid GeO4 tetrahedra and flexible XBa6 octahedra. RSC Adv, 2015, 5: 53448-53454 CrossRef Google Scholar

[54] Zhen N, Wu K, Li Q, et al. Synthesis, structures, and properties of two magnesium silicate fluorides Mg5(SiO4)2F2 and Mg3SiO4F2. New J Chem, 2015, 39: 8866-8873 CrossRef Google Scholar

[55] Yu P, Wu LM, Zhou LJ, et al. Deep-ultraviolet nonlinear optical crystals: Ba3P3O10X (X=Cl, Br). J Am Chem Soc, 2014, 136: 480-487 CrossRef PubMed Google Scholar

[56] Eckardt RC, Byer RL, Masuda H, et al. Absolute and relative nonlinear optical coefficients of KDP, KD*P, BaB2O4, LiIO3, MgO-LiNbO3, and KTP measured by phase-matched secondharmonic generation. IEEE J Quantum Electron, 1990, 26: 922-933 CrossRef ADS Google Scholar

  • Figure 1

    (a) The [BeBO4] layer in SBBO and the 3D crystal structure for SBBO with the bonds of Sr–O being removed; (b) the [LiSi3O9] layer in Li2Cs4Si6O15 and the 3D crystal structure for Li2Cs4Si6O15 with the bonds of Cs–O being removed; (c) the [Ge6O15] layer in Li3Cs3Ge6O15 and the 3D crystal structure for Li3Cs3Ge6O15 with the bonds of Cs–O being removed.

  • Figure 2

    The TG/DSC curves for (a) Li2Rb4Si6O15, (b) Li2Cs4Si6O15, (c) Li3Rb3Ge6O15, (d) Li3Cs3Ge6O15. All data indicate that the title compounds melt congruently.

  • Figure 3

    Phase-matching curves for KDP, Li3Rb3Ge6O15 and Li3Cs3Ge6O15 at 1064 nm, the solid curves are a guide for the eyes and not a fit to the data (a). The SHG signals for KDP, Li3Rb3Ge6O15 and Li3Cs3Ge6O15 in the same particle sizes (b), 0.8×KDP for Li3Rb3Ge6O15 and 1×KDP for Li3Cs3Ge6O15.

  • Figure 4

    Calculated band gaps for (a) Li2Rb4Si6O15, (b) Li2Cs4Si6O15, (c) Li3Rb3Ge6O15, (d) Li3Cs3Ge6O15. They are all direct band gap compounds with the band gaps of 4.33, 4.47, 3.20 and 3.23 eV, respectively.

  • Figure 5

    The densities of states for (a) Li2Rb4Si6O15, (b) Li2Cs4Si6O15, (c) Li3Rb3Ge6O15, (d) Li3Cs3Ge6O15. These indicate that the observed absorptions on their diffuse reflectance spectra mainly originate from the O 2p and Si 3p and Ge 4p states.

  • Table 1   Crystallographic data and structure refinements for LimAnM6O15 (A=Rb, Cs; M=Si, Ge; m+n=6)

    Empirical formula

    Li3Rb3Ge6O15

    Li3Cs3Ge6O15

    Li2Rb4Si6O15

    Li2Cs4Si6O15

    Formula weight

    317.59

    365.03

    764.32

    954.06

    Crystal system

    Orthorhombic

    Orthorhombic

    Monoclinic

    Monoclinic

    Space group

    Pca21

    Pca21

    C2/m

    C2/m

    Unit cell (Å)

    a=17.021(2)

    a=17.1747(15)

    a=18.556(3)

    a=19.0824(10)

    b=6.2304(8)

    b=6.3710(6)

    b=8.3879(13)

    b=8.4878(4)

    c=5.0747(7)

    c=5.1198(4)

    c=10.6839(16)

    c =11.0070(5)

    β=90°

    β=90°

    β=90°

    β=90°

    Z, Volume (Å3)

    4, 538.14(12)

    4, 560.21(8)

    4, 1662.9(5)

    4, 1782.77(15)

    Density (g cm−3)

    3.920

    4.328

    3.053

    3.555

    Absorption coefficient (mm−1)

    20.087

    17.068

    12.208

    8.587

    Goodness-of-fit on F2

    1.226

    1.275

    1.158

    1.344

    Final R indices [Fo2>2s(Fo2)]a

    R1=0.0496,

    wR2=0.1441

    R1=0.0340,

    wR2=0.1078

    R1=0.0780,

    wR2=0.1933

    R1=0.0213,

    wR2=0.0717

    R indices (all data)

    R1=0.0643,

    wR2=0.2018

    R1=0.0406,

    wR2=0.1317

    R1=0.0934,

    wR2=0.2039

    R1=0.0255,

    wR2=0.0827

    R1=Σ||Fo|−|Fc||/Σ|Fo| and wR2=[Σw(Fo2Fc2)2wFo4]1/2 for Fo2 > 2σ(Fo2)

  • Table 2   Direction and magnitude of dipole moments in LiO4 tetrahedra and GeO4 tetrahedra in the unit cell

    Species

    a-axis (D)

    b-axis (D)

    c-axis (D)

    Total (D)

    Li3Rb3Ge6O15

    LiO4

    0

    0

    −1.24

    1.24

    GeO4

    0

    0

    −1.32

    1.32

    Unit cell

    0

    0

    −2.56

    2.56

    Li3Cs3Ge6O15

    LiO4

    −0.38

    0.04

    2.96

    2.99

    GeO4

    0

    0

    1.04

    1.04

    Unit cell

    −0.38

    0.04

    4.01

    4.02

Copyright 2020  CHINA SCIENCE PUBLISHING & MEDIA LTD.  中国科技出版传媒股份有限公司  版权所有

京ICP备14028887号-23       京公网安备11010102003388号