K₅(W₃O₉F₄)(IO₃): An Efficient Mid-Infrared Nonlinear Optical Compound with High Laser Damage Threshold

Abstract

The discovery of nonlinear optical (NLO) materials for generating coherent mid-infrared (mid-IR) light is critically important in developing laser technologies. However, all of the commercialized mid-IR crystals thus far possess problems that have hindered their application. We report herein a function-directing structural design strategy to afford a new type of mid-IR NLO material, using fluorinated 5d0-transition metal octahedra to construct a polar noncentrosymmetric material K5(W3O9F4)­(IO3). The Λ-shaped [W3O12F4]10– polyanion, consisting of distorted octahedra, not only guides the alignment of the [IO3]− units but also serves as a new kind of NLO-active chromophore in the mid-IR, with K5(W3O9F4)­(IO3) possessing an optimal combination of large second-harmonic generation response (11 × KH2PO4@1064 nm and 0.5 × AgGaS2@2100 nm), wide visible and mid-IR transparency (0.32–10.5 μm), and a giant laser damage threshold (95 × AgGaS2). The important role of the [W3O12F4]10– polyanion in improving the NLO properties and extending the IR transparency region has been clarified through first-principles calculations. Our results suggest that the incorporation of fluorinated 5d0-transition metal chromophores into iodate materials may afford a viable route to novel promising mid-IR NLO materials with exceptional NLO functions.

On Prediction of a Novel Chiral Material Y2H3O(OH): A Hydroxyhydride Holding Hydridic and Protonic Hydrogens

“…One sees large peaks of DOS in the wide interval of the valence band, in which the behavior of p oxygen states mimics the hydrogen s states. However, the contribution of O(2) oxygen is narrowed and shifted by ca 2 eV, as compared with the corresponding contribution of O (1). The other feature is that the conduction band, which is formed by contributions of the s empty states of all the elements, is significantly broadened along the energy axis.…”

“…Design of inorganic compounds containing different anions attracts a lot of attention because it provides an opportunity to develop new functionality of material properties [1][2][3][4][5]. Over the past decade, the anion exchange of metal oxide for a hydride ion has become the subject of intensive research in the mixed-anion chemistry [6][7][8][9][10][11].…”

From Ag2Zr(IO3)6 to LaZr(IO3)5F2: A Case of Constructing Wide‐band‐gap Birefringent Materials through Chemical Cosubstitution

“…Furthermore, the band gap of 4.13 eV is similar to that of La (IO 3 ) 3 (4.12 eV) and larger than those of known d 0 À TMcontaining metal iodates such as BaNb(IO 3 ) 5 (3.64 eV), [14] NH 4 MoO 3 (IO 3 ) (3.26 eV), [15] CsVO 2 F(IO 3 ) (2.39 eV), [16] K 5 (W 3 O 9 F 4 ) (IO 3 ) (3.83 eV). [17]…”

“…So far, the introduction of other SOJT distortive cations (V 5+ , Nb 5+ , Bi 3+ , Pb 2+ , etc .) into metal iodates or condensation of IO 3 − and IO 4 3− anions to form polyiodate anions are the two major routes for exploring new metal iodates, which have led to the discovery of many metal iodates with excellent SHG performance [12–33] …”

Helix-constructed polar rare-earth iodate fluoride as a laser nonlinear optical multifunctional material

“…In recent years, metal iodate fluorides have become a research hotspot. Several metal iodate fluoride NLO crystals have been reported, mainly including Bi(IO 3 )F 2 , 5 Bi 3 OF 3 (IO 3 ) 4 , 6 ABi 2 (IO 3 ) 2 F 5 (A = K, Rb, Cs, NH 4 ), 7 β-Ba[VFO 2 (IO 3 ) 2 ], 8 α/β-Ba 2 [VO 2 F 2 (IO 3 ) 2 ]IO 3 , 8 α/β-Ba 2 [GaF 4 (IO 3 ) 2 ](IO 3 ), 9 K 5 (W 3 O 9 F 4 )(IO 3 ), 10 CsVO 2 F(IO 3 ), 11 Ce(IO 3 ) 2 F 2 ·H 2 O, 12 Sn(IO 3 ) 2 F 2 , 13 etc. These metal iodate fluoride NLO crystals generally exhibit a wide transparent range covering the visible to mid-IR region, large SHG effects, and a high laser damage threshold (LDT).…”