View PDF VersionPrevious ArticleNext Article
 
DOI: 10.1039/D1QI01270C (Research Article) Inorg. Chem. Front., 2022, 9, 1224-1232

Enhancement of band gap and birefringence induced via π-conjugated chromophore with “tail effect”†

Wenbing Cai , Jiongquan Chen , Shilie Pan * and Zhihua Yang *
CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, CAS; Xinjiang Key Laboratory of Electronic Information Materials and Devices, Urumqi 830011, China. E-mail: slpan@ms.xjb.ac.cn; zhyang@ms.xjb.ac.cn

Received 8th October 2021 , Accepted 9th November 2021

First published on 12th November 2021

Abstract

Birefringent materials, crucial components in modulating the polarization of light, are of great significance in optical communication and the laser industry. However, it is difficult to dig out excellent material motifs for designing and fabricating novel birefringent materials. In this work, we reassembled the traditional π-groups by structural design, and further proposed a general strategy wherein the introduction of hydrogen into the π-conjugated groups is beneficial to improving birefringence. The planar [HCO3]−/[HBO3]2−/[HC3N3O3]2− groups, obtained by introducing H into the [CO3]2−/[BO3]3−/[C3N3O3]3− groups, exhibit enhanced polarizability anisotropy and comparable HOMO–LUMO energy gap. The carbonates A2CO3 (A = Na, K, Rb, Cs) and K3CO3F, with the [CO3]2− group, and AHCO3 (A = Li, Na, K, Rb) and K2HCO3F·H2O, with the [HCO3]− group, were screened out as targeted materials and investigated by first-principles calculations and experimental verification. With the evolution of the structure of the compounds containing [CO3]− to the compounds containing [HCO3]−, the band gaps and birefringence increase significantly. Particularly, the enhancement in optical anisotropy of CsHCO3 can reach 59.76% as compared to Cs2CO3. Consistent results were also found in Na3BO3/Ca3(C3N3O3)2 to Na2HBO3/Rb2(HC3N3O3). To further clarify the origin of the enhancement in band gap and birefringence, the bonding electron density difference Δρ and electron density difference were analyzed. It is indicated that the enhanced optical anisotropy can be attributed to the “tail effect” of the extended electronic distribution from the [CO3]2−/[BO3]3−/[C3N3O3]3− groups to the [HCO3]−/[HBO3]2−/[HC3N3O3]2− groups. This study offers a new guide to the exploration of outstanding genetic candidates for birefringent materials.

Introduction

Owing to their essential function in modulating the polarization of light, birefringent materials have attracted extensive academic and commercial interest in many branches of science and technology, such as the laser industry, optical communication, polarimetry, and scientific instrumentation.1–6 Typical birefringent materials, including YVO4,7 TiO2,8 CaCO3,9 and α-BaB2O4(BBO),10 have been widely used to produce optical devices (e.g., polarizers, polarization beam displacers, optical isolators, phase compensators, and circulators) working in the spectral regions from the ultraviolet (UV) to the infrared (IR) range.11–13 Recently, with the development of optical technology, birefringent crystals with large optical anisotropy have been a research hotspot in optoelectronic functional materials. In the process of exploring birefringent materials, some theoretical research methods have been applied to push the field forward, such as real-space atom-cutting14 and the response electron distribution anisotropy (REDA) analysis method,15,16 which can be used to quantitatively analyze the contribution of a class of groups to the birefringence. In addition, the origin of birefringence can also be studied on an atomic scale by Born effective charge17,18 and Bader charge analysis methods.19 Simultaneously, some strategies have been proposed to enhance birefringence; for example, introducing (1) π-conjugated planar groups;20–23 (2) stereo-chemically active lone pair electron cations;24–26 (3) synergy of fluorooxo-functional groups and π-conjugated planar groups;27,28 (4) d0 transition metal cations with octahedral coordination under the second-order Jahn–Teller effect or octahedral-coordinated d10 transition metal cations with polar displacement.29,30 Among these, the introduction of planar π-conjugation units is the most effective way to obtain large birefringence. The [BO3]3− group has been regarded as a promising birefringent functional chromophore; many compounds including the [BO3]3− group or its derivatives possess large birefringence, such as KBe2BO3F2 (0.077 at 1064 nm),31γ-Be2BO3F (0.105 at 400 nm),32α-BBO (0.116 at 1064 nm),10β-BBO (0.113 at 1064 nm),33 Na3Ba2(B3O6)2F (0.103 at 1064 nm),34 Ba2Ca(B3O6)2 (0.118 at 1064 nm),35 Li2Na2B2O5 (0.099 at 1064 nm)36 and Ca(BO2)2 (0.120 at 1064).37 Additionally, the synergy of [BO3]3− and [BO3F]4− makes fluorooxoborates such as AB4O6F (A = NH4+, Na, Rb, Cs) possess large birefringence (≈0.112 at 1064 nm).38–41 Besides, the planar [CO3]2− group exhibits high polarizability anisotropy in calcite; a series of carbonates including the [CO3]2− group have been reported and show large birefringence, such as NaZnCO3(OH),42 ABCO3F (A = K, Rb, Cs; B = Mg, Ca, Sr),43 Ca2Na3(CO3)3F44 and RbMgCO3F.45 In addition to the traditional π-conjugated groups, is it possible to further reassemble the π-conjugated groups to form new birefringent functional “genes” to significantly improve optical anisotropy?

In this work, we tried to reassemble the [CO3]2−/[BO3]3−/[C3N3O3]3− groups by structural design. On the basis of a thorough survey of the inorganic crystal structure database (ICSD, Version 4.6.0, build 20210419-1300), three types of compounds were screened out as templates, namely the carbonates (A2CO3, AHCO3 (A = Na, K, Rb, Cs),46–53 K3CO3F54 and K2HCO3F·H2O55), the borates (Na3BO356 and Na2HBO357), and the cyanurates (Ca3(C3N3O3)258 and Rb2(HC3N3O3)59), details of which are in Table S1 of the ESI.† First, the highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) energy gap, polarizability anisotropy, frontier molecular orbital and energy levels of the [CO3]2−, [BO3]3−, [C3N3O3]3−, [HCO3]−, [HBO3]2− and [HC3N3O3]2− groups were explored to evaluate the potential of [HCO3]−/[HBO3]2−/[HC3N3O3]2− as promising birefringent functional units. It was found that the [HCO3]−/[HBO3]2−/[HC3N3O3]2− groups exhibit larger polarizability anisotropy than the [CO3]2−/[BO3]3−/[C3N3O3]3− groups. Subsequently, the properties of the targeted materials A2CO3, AHCO3 (A = Li, Na, K, Rb), K3CO3F and K2HCO3F·H2O were investigated via first-principles calculations and/or experimental verification, indicating that with the transformation of compounds with [CO3]2− to ones with [HCO3]−, the band gaps and birefringence increased significantly. In addition, enhancement in band gap and linear optical properties were also found in Na3BO3/Ca3(C3N3O3)2 to Na2HBO3/Rb2(HC3N3O3). To further clarify the origin of the enhancement in band gap and birefringence, the bonding electron density difference Δρ and the electron density difference were analyzed.

Methods

Calculation method

First-principles calculations were performed by the plane-wave pseudo-potential method implemented in the CASTEP package.60 Band structures and optical properties were calculated via the Perdew–Burke–Ernzerhof (PBE) functional in the scheme of generalized gradient approximation (GGA).61 Norm-conserving pseudopotentials62 were employed for each atomic species with the following valence electronic configurations: Na 2s2 2p6 3s1, K 3s2 3p6 4s1, Ca 3s2 3p6 4s2, Rb 4s2 4p6 5s1, Cs 5s2 5p6 6s1, B 2s2 2p1, C 2s2 2p2, N 2s2 2p3, O 2s2 2p4, F 2s2 2p5, and H 1s1. The plane-wave cut-off energy of A2CO3, AHCO3 (A = Li, Na, K, Rb), Na3BO3, Na2HBO3, Ca3(C3N3O3)2 and Rb2(HC3N3O3) was 750 eV, with 850 eV for K3CO3F and K2HCO3F·H2O. To achieve a good convergence of electronic structures and optical properties, a dense k-point sampling of less than 0.03 Å−1 for the template compounds was adopted. The other calculated parameters and convergent criteria were set by the default values of the CASTEP code. Our tests revealed that the computational parameters mentioned above are sufficiently accurate for the present calculations.

The contribution of groups to the birefringence can be analyzed through the REDA method.15,16 Compared to other methods, this method takes into account the density and arrangement of groups. Birefringence is proportional to the REDA index: image file: d1qi01270c-t1.tif, where Nc is the coordination number of the nearest neighbour cations to the central anion, Za is the formal chemical valence of the anion, Δρb is the difference in covalent electron density of the covalent bond i on the optical principal axes of a crystal, n1 is the minimal refractive index, and Eg is the optical band gap.

Experimental method

The UV-Vis-NIR diffuse-reflectance spectrum was recorded by a SolidSpec-3700DUV spectrophotometer at room temperature with scanning wavelengths over the range of 190 to 2600 nm. The absorption data were obtained by the Kubelka–Munk relation function: F(R) = (1 − R)2/2R = K/S, where R is the reflectance, K is the absorption, and S is the scattering.

Results and discussion

Evaluation of [HCO3]−/[HBO3]2−/[HC3N3O3]2− groups as promising birefringent chromophores

First, the HOMO–LUMO energy gap, polarizability anisotropy, frontier molecular orbitals and energy levels of the [CO3]2−, [BO3]3−, [C3N3O3]3−, [HCO3]−, [HBO3]2− and [HC3N3O3]2− groups were investigated by the quantum chemistry software package Gaussian 09.63 To get more universal insights, the obtained units from the primary crystal structures were further optimized. Taking the [CO3]2− and [HCO3]− groups as representative illustrations, the energy levels in Fig. 1 show that the [CO3]2− and [HCO3]− groups have extremely large HOMO–LUMO energy gaps of 7.34 eV and 7.04 eV, respectively. The lone pair (LP) 2p orbitals of the O atoms and the antibonding (BD*) orbitals of the C–O bonds occupy the HOMO and the LUMO of the [CO3]2− and [HCO3]− groups, respectively. The HOMO and LUMO can also be further identified by frontier molecular orbitals. It is evident that the HOMO is mainly occupied by the nonbonding orbitals of O-2p, while the LUMO consists of the anti-π bonds of the C–O bonds. Additionally, in [HCO3]−, the bonding (BD) and BD* orbitals of the O–H bonds locate far away from the HOMO and LUMO. Similar results for [BO3]3−, [C3N3O3]3−, [HBO3]2− and [HC3N3O3]2−can be found in Fig. S1.†
image file: d1qi01270c-f1.tif
Fig. 1 The HOMO–LUMO energy gaps, frontier molecular orbitals (MOs) and energy levels of [CO3]2− (a) and [HCO3]− (b).

Moreover, the polarizability anisotropy of the groups can be acquired from static polarization according to the following formula:

image file: d1qi01270c-t2.tif
where α is the static polarization and Δα is the polarizability anisotropy. Table S2† shows the static polarization component, polarizability anisotropy and HOMO–LUMO energy gap of the groups. The polarizability anisotropies Δα of the [HCO3]−, [HBO3]2− and [HC3N3O3]2− groups (17.12, 15.51 and 54.53) are slightly larger than those of the [CO3]2−, [BO3]3− and [C3N3O3]3− groups (12.79, 9.44 and 51.19). The [CO3]2− unit has been recognized as a promising birefringent chromophore; the birefringence of the benchmark birefringent material CaCO3 can reach 0.171 at 633 nm. The comparable Δα of [HCO3]−, [HBO3]2− and [HC3N3O3]2− with that of [CO3]2−, [BO3]3− and [C3N3O3]3− indicates that the [HCO3]−, [HBO3]2− or [HC3N3O3]2− units can also be birefringent chromophores.

Band structures and electronic structures

The GGA electronic band structures of the target compounds along the high symmetry lines in the Brillouin zone are displayed in Fig. S2 of the ESI.† Owing to the underestimated calculated band gap using the GGA functional,64–66 the HSE06 functional was employed to gain more accurate band gap values. The calculated values using the HSE06 functional of A2CO3 (A = Na, K, Rb, Cs) and K3CO3F are 5.61 eV, 5.51 eV, 5.23 eV, 3.78 eV and 5.60 eV. The calculated values using the HSE06 functional of AHCO3 (A = Na, K, Rb, Cs) and K2HCO3F·H2O are 7.01 eV, 6.95 eV, 6.64 eV, 6.68 eV and 6.66 eV, which means they can achieve deep-UV transparency. To further verify the calculated values, the UV-Vis-NIR diffuse-reflectance spectra of A2CO3 and AHCO3 (A = Na, K) were measured, as shown in Fig. 2 and Fig. S3,† and the measurement results exhibit that the experimental band gaps of Na2CO3, NaHCO3, K2CO3 and KHCO3 are 6.05 eV, 6.20 eV, 5.68 eV and 6.13 eV, respectively, which are well consistent with the calculated values.
image file: d1qi01270c-f2.tif
Fig. 2 The UV-Vis-NIR diffuse reflectance spectra of K2CO3 (a) and KHCO3 (b), the insets indicate experimental band gap values.

The partial density of states (PDOS) of A2CO3, AHCO3 (A = Na, K, Rb, Cs), K3CO3F and K2HCO3F·H2O are shown in Fig. 3 and Fig. S4.† Taking K2CO3 as an example, the main states that determine the band gap and electronic transitions are in the range of −10 to 10 eV near the Fermi surface. The top of the valence bands (VBs) is mainly composed of O-2p orbitals and the bottom of the conduction bands (CBs) is greatly derived from C-2p and O-2p orbitals; a small fraction of orbitals of K atoms are also mixed in the CBs. It is well known that electron transitions near the Fermi surface determine optical properties,67–69 and it can be expected that the [CO3]2− groups play a significant role in the optical origin of K2CO3. Based on the same analysis, similar electronic states were also found in KHCO3 and the other eight compounds.


image file: d1qi01270c-f3.tif
Fig. 3 The partial density of states (PDOS) of K2CO3 (a) and KHCO3 (b).

Optical anisotropy

The linear optical performances of A2CO3, AHCO3 (A = Na, K, Rb, Cs), K3CO3F and K2HCO3F·H2O are shown in Fig. 4. It can be found that the birefringence of A2CO3 (A = Na, K, Rb, Cs) and K3CO3F is 0.144, 0.113, 0.107, 0.082 and 0.085 at 1064 nm, and the birefringence of AHCO3 (A = Na, K, Rb, Cs) and K2HCO3F·H2O is 0.202, 0.172, 0.164, 0.131 and 0.095 at 1064 nm, respectively. Na2CO3 and NaHCO3 have, respectively, the largest birefringence among the two types of compounds including [CO3]2− or [HCO3]−. Upon the transformation of A2CO3 (A = Na, K, Rb, Cs) and K3CO3F to AHCO3 (A = Na, K, Rb, Cs) and K2HCO3F·H2O, the birefringence increases significantly, among which CsHCO3 can attain an increase of 59.76% as compared to Cs2CO3. In addition, the birefringence of NaHCO3 can reach 0.202 at 1064 nm, larger than that of LiNbO3 (0.089 at 1064 nm),70α-BBO (0.116 at 1064 nm),10 and CaCO3 (0.164 at 1064 nm),9 and comparable to that of YVO4 (0.210 at 1064 nm)7 and TiO2 (0.256 at 1530 nm).8
image file: d1qi01270c-f4.tif
Fig. 4 Birefringence of A2CO3 (A = Na, K, Rb, Cs), K3CO3F (a), and birefringence of AHCO3 (A = Na, K, Rb, Cs), K2HCO3F·H2O (b).

Analysis of the optical origin

The REDA method was also adopted for optical anisotropy analysis. The bonding electron density difference Δρ of A-site cationic polyhedra and the anionic groups [CO3]2− or [HCO3]− on the optical principal axes was researched. Details of the REDA analysis results are listed in Table S3 of the ESI.† As shown in Fig. 5, for K2CO3, the Δρ of the kalium-oxygen polyhedra and [CO3]2− units is 0.01913 and 0.00160, respectively, which indicates that the [CO3]2− units cause approximately 92.28% contribution to the birefringence. Similar results were also found in Na2CO3, Rb2CO3, Cs2CO3 and K3CO3F. For KHCO3, the Δρ of the [NaO6] polyhedra and [HCO3]− units is −0.00093 and 0.03391, respectively. When it comes to K2HCO3F·H2O, the Δρ of the cationic polyhedra, [HCO3]− units and H2O molecules is −0.00049, 0.02584 and 0.00813, respectively. The results imply that the [HCO3]− units are the main contributors to birefringence. In addition, in K2HCO3F·H2O, the contribution of H2O molecules should not be ignored because they contribute about 24% to birefringence.
image file: d1qi01270c-f5.tif
Fig. 5 Contribution of groups of the targeted compounds to optical anisotropy by the REDA analysis method.

Discussion

Unexpectedly, from compounds including the [CO3]2− group to compounds with the [HCO3]− group, the band gap and birefringence enhance obviously. We were curious to see whether this enhancement also appears in borate or other systems Therefore, the band gaps, birefringence and bond electron density differences Δρ of Na3BO3, Na2HBO3, Ca3(C3N3O3)2 and Rb2(HC3N3O3) were further calculated and analyzed. As shown in Fig. 6 and Table S4,† the same results can be found from Na3BO3/Ca3(C3N3O3)2 to Na2HBO3/Rb2(HC3N3O3). Additionally, birefringence is positively related to the bonding electron density difference Δρ. This indicates that the introduction of H into the π-conjugated groups of [CO3]2−/[BO3]3−/[C3N3O3]3− can further enhance the bonding electron density difference Δρ due to the “tail effect” to extend the electronic distribution of the π-conjugated groups, which can be further visualized by the electron density difference of the microscopic groups with or without hydrogen, as shown in Fig. 7.
image file: d1qi01270c-f6.tif
Fig. 6 Birefringence obtained by the first-principles calculations with respect to the bonding electron density difference Δρ of the template compounds.

image file: d1qi01270c-f7.tif
Fig. 7 The electron density differences of the [BO3]3−, [HBO3]2−, [CO3]2−, [HCO3]−, [C3N3O3]3− and [HC3N3O3]2− groups.

Conclusion

In conclusion, a general strategy that introduces hydrogen into the π-conjugated groups was proposed to enhance optical anisotropy. The potential of [HCO3]−/[HBO3]2−/[HC3N3O3]2− groups as promising birefringent functional chromophores was evaluated and shows superiority in designing birefringent materials. The theoretical and experimental results demonstrate that the after the structural evolution of A2CO3 (A = Li, Na, K, Rb) and K3CO3F with the [CO3]2− group to AHCO3 (A = Li, Na, K, Rb) and K2HCO3F·H2O with the [HCO3]− group, their band gaps and birefringence increase obviously. Moreover, the enhancement was also found in other systems, such as Na3BO3/Ca3(C3N3O3)2 to Na2HBO3/Rb2(HC3N3O3). The improved optical anisotropy can be attributed to the extended electronic density distribution as the “tail effect” caused by structural design, which is the introduction of hydrogen into the traditional π-conjugated groups. This strategy offers a new guide to the discovery of advanced optical materials.

Conflicts of interest

There are no conflicts to declare.

Acknowledgements

This work is supported by the West Light Foundation of the Chinese Academy of Sciences (Grant no. 2019-YDYLTD-002), National Natural Science Foundation of China (51922014, 51972336 and 61835014), Key Research Program of Frontier Sciences, CAS (ZDBS-LY-SLH035), and the International Partnership Program of Chinese Academy of Sciences (1A1365KYSB20200008).

Notes and references

  1. M. F. Weber, C. A. Stover, L. R. Gilbert, T. J. Nevitt and A. J. Ouderkirk, Giant Birefringent Optics in Multilayer Polymer Mirrors, Science, 2000, 287, 2451–2456 CrossRef CAS PubMed .
  2. D. Brida, C. Manzoni and G. Cerullo, Phase-Locked Pulses for Two-Dimensional Spectroscopy by a Birefringent Delay Line, Opt. Lett., 2012, 37, 3027–3029 CrossRef PubMed .
  3. S. Y. Niu, G. Joe, H. Zhao, Y. C. Zhou, T. Orvis, H. X. Huyan, J. Salman, K. Mahalingam, B. Urwin, J. B. Wu, Y. Liu, T. E. Tiwald, S. B. Cronin, B. M. Howe, M. Mecklenburg, R. Haiges, D. J. Singh, H. Wang, M. A. Kats and J. Ravichandran, Giant Optical Anisotropy in a Quasi-One-Dimensional Crystal, Nat. Photonics, 2018, 12, 392–396 CrossRef CAS .
  4. G. H. Zou, C. S. Lin, H. Jo, G. Nam, T. S. You and K. M. Ok, Pb2BO3Cl: A Tailor-Made Polar Lead Borate Chloride with Very Strong Second Harmonic Generation, Angew. Chem., Int. Ed., 2016, 55, 12078–12082 CrossRef CAS PubMed .
  5. R. L. Tang, C. L. Hu, B. L. Wu, Z. Fang, Y. Chen and J. G. Mao, 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 CAS PubMed .
  6. H. C. Lu, R. Gautier, M. D. Donakowski, T. T. Tran, B. W. Edwards, J. C. Nino, P. S. Halasyamani, Z. T. Liu and K. R. Poeppelmeier, Nonlinear Active Materials: An Illustration of Controllable Phase Matchability, J. Am. Chem. Soc., 2013, 135, 11942–11950 CrossRef CAS PubMed .
  7. H. T. Luo, T. Tkaczyk, E. L. Dereniak, K. Oka and R. Sampson, High birefringence of the yttrium vanadate crystal in the middle wavelength infrared, Opt. Lett., 2006, 31, 616–618 CrossRef CAS PubMed .
  8. J. R. Devore, Refractive indices of rutile and sphalerite, J. Opt. Soc. Am., 1951, 41, 416–419 CrossRef CAS .
  9. G. Ghosh, Dispersion-equation coefficients for the refractive index and birefringence of calcite and quartz crystals, Opt. Commun., 1999, 163, 95–102 CrossRef CAS .
  10. G. Q. Zhou, J. Xu, X. D. Chen, H. Y. Zhong, S. T. Wang, K. Xu, P. Z. Deng and F. X. Gan, Growth and spectrum of a novel birefringent α-BaB2O4 crystal, J. Cryst. Growth, 1998, 191, 517–519 CrossRef CAS .
  11. K. Aoki, H. T. Miyazaki, H. Hirayama, K. Inoshita, T. Baba, K. Sakoda, N. Shinya and Y. Aoyagi, Microassembly of Semiconductor Three-Dimensional Photonic Crystals, Nat. Mater., 2003, 2, 117–121 CrossRef CAS PubMed .
  12. S. Ghosh, W. H. Wang, F. M. Mendoza, R. C. Myers, X. Li, N. Samarth, A. C. Gossard and D. D. Awschalom, Enhancement of Spin Coherence Using Q-Factor Engineering in Semiconductor Microdisc Lasers, Nat. Mater., 2006, 5, 261–264 CrossRef CAS PubMed .
  13. Z. Y. Xie, L. G. Sun, G. Z. Han and Z. Z. Gu, Optical Switching of a Birefringent Photonic Crystal, Adv. Mater., 2008, 20, 3601–3604 CrossRef CAS .
  14. J. Lin, M. H. Lee, Z. P. Liu, C. T. Chen and C. J. Pickard, Mechanism for Linear and Nonlinear Optical Effects In β−BaB2O4 crystals, Phys. Rev. B: Condens. Matter Mater. Phys., 1999, 60, 13380–13389 CrossRef CAS .
  15. B. H. Lei, Z. H. Yang and S. L. Pan, Enhancing Optical Anisotropy of Crystals by Optimizing Bonding Electron Distribution in Anionic Groups, Chem. Commun., 2017, 53, 2818–2821 RSC .
  16. B. H. Lei, Z. H. Yang, H. W. Yu, C. Cao, Z. Li, C. Hu, K. R. Poeppelmeier and S. L. Pan, Module-Guided Design Scheme for Deep-Ultraviolet Nonlinear Optical Materials, J. Am. Chem. Soc., 2018, 140, 10726–10733 CrossRef CAS PubMed .
  17. N. A. Spaldin, A Beginner's Guide to the Modern Theory of Polarization, J. Solid State Chem., 2012, 195, 2–10 CrossRef CAS .
  18. Q. Jing, G. Yang, J. Hou, M. Z. Sun and H. B. Cao, Positive and Negative Contribution to Birefringence in a Family of Carbonates: A Born Effective Charges Analysis, J. Solid State Chem., 2016, 244, 69–74 CrossRef CAS .
  19. C. S. Lin, A. Y. Zhou, W. D. Cheng, N. Ye and G. L. Chai, Atom-Resolved Analysis of Birefringence of Nonlinear Optical Crystals by Bader Charge Integration, J. Phys. Chem. C, 2019, 123, 31183–31189 CrossRef CAS .
  20. Y. C. Liu, Y. G. Shen, S. G. Zhao and J. H. Luo, Structure-Property Relationship in Nonlinear Optical Materials with π-Conjugated CO3 Triangles, Coord. Chem. Rev., 2020, 407, 213152–213172 CrossRef CAS .
  21. Y. G. Shen, S. G. Zhao and J. H. Luo, The Role of Cations in Second-Order Nonlinear Optical Materials Based on π-Conjugated [BO3]3− Groups, Coord. Chem. Rev., 2018, 366, 1–28 CrossRef CAS .
  22. X. M. Liu, P. F. Gong, Y. Yang, G. M. Song and Z. S. Lin, Nitrate Nonlinear Optical Crystals: A Survey on Structure-Performance Relationships, Coord. Chem. Rev., 2019, 400, 213045–213059 CrossRef CAS .
  23. F. Liang, L. Kang, X. Y. Zhang, M. H. Lee, Z. S. Lin and Y. C. Wu, Molecular Construction Using (C3N3O3)3− Anions: Analysis and Prospect for Inorganic Metal Cyanurates Nonlinear Optical Materials, Cryst. Growth Des., 2017, 17, 4015–4020 CrossRef CAS .
  24. J. Y. Guo, A. Tudi, S. J. Han, Z. H. Yang and S. L. Pan, Sn2B5O9Cl: A Material with Large Birefringence Enhancement Activated Prepared Via Alkaline-Earth-Metal Substitution by Tin, Angew. Chem., Int. Ed., 2019, 58, 17675–17678 CrossRef CAS PubMed .
  25. J. Y. Guo, A. Tudi, S. J. Han, Z. H. Yang and S. L. Pan, α-SnF2: A UV Birefringent Material with Large Birefringence and Easy Crystal Growth, Angew. Chem., Int. Ed., 2021, 60, 3540–3544 CrossRef CAS PubMed .
  26. Y. Yang, Y. Qiu, P. F. Gong, L. Kang, G. M. Song, X. M. Liu, J. L. Sun and Z. Lin, Lone-Pair Enhanced Birefringence in an Alkaline-Earth Metal Tin(II) Phosphate BaSn2(PO4)2, Chem. – Eur. J., 2019, 25, 5648–5651 CrossRef CAS PubMed .
  27. Z. H. Yang, A. Tudi, B.-H. Lei and S. L. Pan, Enhanced Nonlinear Optical Functionality in Birefringence and Refractive Index Dispersion of the Deep-Ultraviolet Fluorooxoborates, Sci. China Mater., 2020, 63, 1480–1488 CrossRef CAS .
  28. B. B. Zhang, G. Q. Shi, Z. H. Yang, F. F. Zhang and S. L. Pan, Fluorooxoborates: Beryllium-Free Deep-Ultraviolet Nonlinear Optical Materials without Layered Growth, Angew. Chem., Int. Ed., 2017, 56, 3916–3919 CrossRef CAS PubMed .
  29. J. B. Huang, S. R. Guo, Z. Z. Zhang, Z. H. Yang and S. L. Pan, Designing Excellent Mid-Infrared Nonlinear Optical Materials with Fluorooxo-Functional Group of d0 Transition Metal Oxyfluorides, Sci. China Mater., 2019, 62, 1798–1806 CrossRef CAS .
  30. B. L. Wu, C. L. Hu, F. F. Mao, R. L. Tang and J. G. Mao, Highly Polarizable Hg2+ Induced a Strong Second Harmonic Generation Signal and Large Birefringence in LiHgPO4, J. Am. Chem. Soc., 2019, 141, 10188–10192 CrossRef CAS PubMed .
  31. B. C. Wu, D. Y. Tang, N. Ye and C. T. Chen, Linear and Nonlinear Optical Properties of the KBe2BO3F2 (KBBF) Crystal, Opt. Mater., 1996, 5, 105–109 CrossRef CAS .
  32. G. Peng, N. Ye, Z. S. Lin, L. Kang, S. L. Pan, M. Zhang, C. S. Lin, X. F. Long, M. Luo, Y. Chen, Y. H. Tang, F. Xu and T. Yan, 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 CAS PubMed .
  33. H. P. Li, C. H. Kam, Y. L. Lam and W. Ji, Femtosecond Z-Scan Measurements of Nonlinear Refraction in Nonlinear Optical Crystals, Opt. Mater., 2001, 15, 237–242 CrossRef CAS .
  34. H. Zhang, M. Zhang, S. L. Pan, Z. H. Yang, Z. Wang, Q. Bian, X. L. Hou, H. W. Yu, F. F. Zhang, K. Wu, F. Yang, J. Q. Peng, Z. Y. Xu, K. B. Chang and K. R. Poeppelmeier, Na3Ba2(B3O6)2F: Next Generation of Deep-Ultraviolet Birefringent Materials, Cryst. Growth Des., 2015, 15, 523–529 CrossRef CAS .
  35. Z. Jia, N. N. Zhang, Y. Y. Ma, L. W. Zhao, M. J. Xia and R. K. Li, Top-Seeded Solution Growth and Optical Properties of Deep-UV Birefringent Crystal Ba2Ca(B3O6)2, Cryst. Growth Des., 2017, 17, 558–562 CrossRef CAS .
  36. M. Zhang, D. H. An, C. Hu, X. L. Chen, Z. H. Yang and S. L. Pan, Rational Design Via Synergistic Combination Leads to an Outstanding Deep-Ultraviolet Birefringent Li2Na2B2O5 Material with an Unvalued B2O5 Functional Gene, J. Am. Chem. Soc., 2019, 141, 3258–3264 CrossRef CAS PubMed .
  37. X. L. Chen, B. B. Zhang, F. F. Zhang, Y. Wang, M. Zhang, Z. H. Yang, K. R. Poeppelmeier and S. L. Pan, Designing an Excellent Deep-Ultraviolet Birefringent Material for Light Polarization, J. Am. Chem. Soc., 2018, 140, 16311–16319 CrossRef CAS PubMed .
  38. G. Q. Shi, Y. Wang, F. F. Zhang, B. B. Zhang, Z. H. Yang, X. L. Hou, S. L. Pan and K. R. Poeppelmeier, Finding the Next Deep-Ultraviolet Nonlinear Optical Material: NH4B4O6F, J. Am. Chem. Soc., 2017, 139, 10645–10648 CrossRef CAS PubMed .
  39. Z. Z. Zhang, Y. Wang, B. B. Zhang, Z. H. Yang and S. L. Pan, Polar Fluorooxoborate, NaB4O6F: A Promising Material for Ionic Conduction and Nonlinear Optics, Angew. Chem., Int. Ed., 2018, 57, 6577–6581 CrossRef CAS PubMed .
  40. Y. Wang, B. B. Zhang, Z. H. Yang and S. L. Pan, Cation-Tuned Synthesis of Fluorooxoborates: Towards Optimal Deep-Ultraviolet Nonlinear Optical Materials, Angew. Chem., Int. Ed., 2018, 57, 2150–2154 CrossRef CAS PubMed .
  41. X. F. Wang, Y. Wang, B. B. Zhang, F. F. Zhang, Z. H. Yang and S. L. Pan, CsB4O6F: A Congruent-Melting Deep-Ultraviolet Nonlinear Optical Material by Combining Superior Functional Units, Angew. Chem., Int. Ed., 2017, 56, 14119–14123 CrossRef CAS PubMed .
  42. G. Peng, C. S. Lin and N. Ye, NaZnCO3(OH): A High-Performance Carbonate Ultraviolet Nonlinear Optical Crystal Derived from KBe2BO3F2, J. Am. Chem. Soc., 2020, 142, 20542–20546 CrossRef CAS PubMed .
  43. G. H. Zou, N. Ye, L. Huang and X. S. Lin, Alkaline-Alkaline Earth Fluoride Carbonate Crystals ABCO3F (A=K, Rb, Cs; B=Ca, Sr, Ba) as Nonlinear Optical Materials, J. Am. Chem. Soc., 2011, 133, 20001–20007 CrossRef CAS PubMed .
  44. M. Luo, Y. X. Song, C. S. Lin, N. Ye, W. D. Cheng and X. F. Long, Molecular Engineering as an Approach to Design a New Beryllium-Free Fluoride Carbonate as a Deep-Ultraviolet Nonlinear Optical Material, Chem. Mater., 2016, 28, 2301–2307 CrossRef CAS .
  45. T. T. Tran, J. G. He, J. M. Rondinelli and P. S. Halasyamani, RbMgCO3F: A New Beryllium-Free Deep-Ultraviolet Nonlinear Optical Material, J. Am. Chem. Soc., 2015, 137, 10504–10507 CrossRef CAS PubMed .
  46. N. V. Zubkova, D. Y. Pushcharovsky, M. G. Ivaldi, G. Ferraris, I. V. Pekov and N. V. Chukanov, Crystal Structure of Natrite, γ-Na2CO3, Neues Jahrb. für Mineral. Monatshefte, 2002, 2, 85–96 CrossRef .
  47. Y. Idemoto, J. W. Richardson, N. Koura, S. Kohara and C. K. Loong, Crystal Structure of (LixK1-x)2CO3 (X=0, 0.43, 0.5, 0.62, 1) by Neutron Powder Diffraction Analysis, J. Phys. Chem. Solids, 1998, 59, 363–376 CrossRef CAS .
  48. R. E. Dinnebier, S. Vensky, M. Jansen and J. C. Hanson, Crystal Structures and Topological Aspects of the High-Temperature Phases and Decomposition Products of the Alkali-Metal Oxalates M2[C2O4] (M=K, Rb, Cs), Chem. – Eur. J., 2005, 11, 1119–1129 CrossRef CAS PubMed .
  49. R. J. Cohen, D. L. Fox, J. F. Eubank and R. N. Salvatore, Mild and Efficient Cs2CO3-Promoted Synthesis of Phosphonates, Tetrahedron Lett., 2003, 44, 8617–8621 CrossRef CAS .
  50. B. D. Sharma, Sodium Bicarbonate and Its Hydrogene Atom, Acta Crystallogr., 1965, 18, 818–819 CrossRef CAS .
  51. S. Kashida and K. Yamamoto, Structural Phase Transition in KHCO3, J. Solid State Chem., 1990, 86, 180–187 CrossRef CAS .
  52. R. Iizuka-Oku, W. Gui, K. Komatsu, T. Yagi and H. Kagi, High-Pressure Responses of Alkali Metal Hydrogen Carbonates, RbHCO3 and CsHCO3: Findings of New Phases and Unique Compressional Behavior, J. Solid State Chem., 2020, 283, 121139–121150 CrossRef CAS .
  53. M. Richter, Y. K. Krisnandi, R. Eckelt and A. Martin, Homogeneously Catalyzed Batch Reactor Glycerol Etherification by CsHCO3, Catal. Commun., 2008, 9, 2112–2116 CrossRef CAS .
  54. J. Arlt and M. Jansen, Einkristallzüchtung and Röntgenstrukturanalyse der Fluoridcarbonate K3CO3F and Rb3CO3F, Z. Naturforsch., B: J. Chem. Sci., 1990, 45, 943–946 CrossRef CAS .
  55. V. Kahlenberg and T. Schwaier, Dipotassium Hydrogencarbonate Fluoride Monohydrate, Acta Crystallogr., Sect. E: Struct. Rep. Online, 2013, 69, i20–i29 CrossRef CAS PubMed .
  56. H. Konig and R. Hoppe, Zur Kenntnis Von Na3BO3, Z. Anorg. Allg. Chem., 1977, 434, 225–232 CrossRef .
  57. S. Menchetti and C. Sabelli, Structure of Hydrated Sodium Borate Na2[BO2(OH)], Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem., 1982, 38, 1282–1285 CrossRef .
  58. M. Kalmutzki, M. Strobele, F. Wackenhut, A. J. Meixner and H. J. Meyer, Synthesis, Structure, and Frequency-Doubling Effect of Calcium Cyanurate, Angew. Chem., Int. Ed., 2014, 53, 14260–14263 CrossRef CAS PubMed .
  59. J. Lu, Y. K. Lian, L. Xiong, Q. R. Wu, M. Zhao, K. X. Shi, L. Chen and L. M. Wu, How to Maximize Birefringence and Nonlinearity of π-Conjugated Cyanurates, J. Am. Chem. Soc., 2019, 141, 16151–16159 CrossRef CAS PubMed .
  60. S. J. Clark, M. D. Segall, C. J. Pickard, P. J. Hasnip, M. J. Probert, K. Refson and M. C. Payne, First Principles Methods Using CASTEP, Z. Kristallogr. – Cryst. Mater., 2005, 220, 567–570 CrossRef CAS .
  61. J. P. Perdew, K. Burke and M. Ernzerhof, Generalized Gradient Approximation Made Simple, Phys. Rev. Lett., 1996, 77, 3865–3868 CrossRef CAS PubMed .
  62. J. S. Lin, A. Qteish, M. C. Payne and V. Heine, Optimized and Transferable Nonlocal Separable Ab Initio Pseudopotentials, Phys. Rev. B: Condens. Matter Mater. Phys., 1993, 47, 4174–4180 CrossRef PubMed .
  63. M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R. Cheeseman, G. Scalmani, V. Barone, B. Mennucci, G. A. Petersson, H. Nakatsuji, M. Caricato, X. Li, H. P. Hratchian, A. F. Izmaylov, J. Bloino, G. Zheng, J. L. Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven, J. A. Montgomery, Jr., J. E. Peralta, F. Ogliaro, M. Bearpark, J. J. Heyd, E. Brothers, K. N. Kudin, V. N. Staroverov, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi, N. Rega, J. M. Millam, M. Klene, J. E. Knox, J. B. Cross, V. Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J. W. Ochterski, R. L. Martin, K. Morokuma, V. G. Zakrzewski, G. A. Voth, P. Salvador, J. J. Dannenberg, S. Dapprich, A. D. Daniels, O. Farkas, J. B. Foresman, J. V. Ortiz, J. Cioslowski and D. J. Fox, Gaussian 09, Revision A.02, Gaussian, Inc., Wallingford CT 2009 Search PubMed .
  64. D. Vanderbilt, Soft Self-Consistent Pseudopotentials in a Generalized Eigenvalue Formalism, Phys. Rev. B: Condens. Matter Mater. Phys., 1990, 41, 7892–7895 CrossRef PubMed .
  65. Z. H. Levine and D. C. Allan, Quasiparticle Calculation of the Dielectric Response of Silicon and Germanium, Phys. Rev. B: Condens. Matter Mater. Phys., 1991, 43, 4187–4207 CrossRef CAS PubMed .
  66. A. J. Cohen, P. Mori-Sanchez and W. T. Yang, Insights into Current Limitations of Density Functional Theory, Science, 2008, 321, 782–794 Search PubMed .
  67. G. S. Painter and D. E. Ellis, Electronic Band Structure and Optical Properties of Graphite from a Variational Approach, Phys. Rev. B: Solid State, 1970, 1, 4747–4752 CrossRef .
  68. D. Adler and J. Feinleib, Electrical and Optical Properties of Narrow-Band Materials, Phys. Rev. B: Solid State, 1970, 2, 3112–3134 CrossRef .
  69. R. C. Tatar and S. Rabii, Electronic Properties of Graphite: A Unified Theoretical Study, Phys. Rev. B: Condens. Matter Mater. Phys., 1982, 25, 4126–4141 CrossRef CAS .
  70. H. Kimura, H. Koizumi, T. Uchida and S. Uda, Influence of Impurity Doping on the Partitioning of Intrinsic Ionic Species During the Growth of LiNbO3 Crystal from the Melt, J. Cryst. Growth, 2009, 311, 1553–1558 CrossRef CAS .

Footnote

† Electronic supplementary information (ESI) available: ICSD code, space group, cell volume and group density of A2CO3, AHCO3, (A = Na, K, Rb, Cs), K3CO3F, K2HCO3F·H2O, Na3BO3, Na2HBO3, Ca3(C3N3O3)2 and Rb2(HC3N3O3). Static polarization component, polarizability anisotropy Δα and HOMO-LUMO energy gap of [CO3]2−, [BO3]3−, [C3N3O3]3−, [HCO3]−, [HBO3]2− and [HC3N3O3]2− groups. The contribution of anionic groups and A-site cationic polyhedra to birefringence. Electronic band structure and PDOS of targeted compounds. Band gap values, birefringence and bonding electron density difference Δρ of Na3BO3, Na2HBO3, Ca3(C3N3O3)2 and Rb2(HC3N3O3). See DOI: 10.1039/d1qi01270c
This journal is © the Partner Organisations 2022
Click here to see how this site uses Cookies. View our privacy policy here.