Single-crystal structures and optical properties of the nonlinear optical KTiOPO{sub 4}-type materials K{sub 0.55}Li{sub 0.45}TiOPO{sub 4} and K{sub 0.54}Li{sub 0.46}TiOAsO{sub 4} prepared by molten salt ion-exchange

Journal Article · Thu May 01 00:00:00 EDT 1997 · Chemistry of Materials

DOI:https://doi.org/10.1021/cm960529o· OSTI ID:569164

Harrison, W T.A. ^[1]; Phillips, M L.F. ^[2]; Stucky, G D ^[3]

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1. Univ. of Western Australia, Nedlands (Australia)
2. Sandia National Labs., Albuquerque, NM (United States)
3. Univ. of California, Santa Barbara, CA (United States)

Single crystals of the KTiOPO{sub 4} (KTP) type phases K{sub 0.55}Li{sub 0.45}TiOPO{sub 4} and K{sub 0.54}Li{sub 0.46}TiOAsO{sub 4} have been prepared by molten salt ion-exchange reactions from their potassium-containing precursors. After ion-exchange both phases maintain the distinctive distorted TiO{sub 6} octahedra seen in KTiOPO{sub 4} and KTiOAsO{sub 4}. The pattern of lithium-ion substitution differs for these two phases: In K{sub 0.55}Li{sub 0.45}TiOPO{sub 4}, Li substitutes for both of the two crystallographically distinct potassium cations to roughly equal extent, whereas in K{sub 0.54}Li{sub 0.46}TiOAsO{sub 4}, the 9-coordinate K(2) atom is preferentially replaced by Li. The lithium cations occupy six-rings of TiO{sub 6} and PO{sub 4} polyhedra and adopt approximate square-planar coordination in both these materials. Second harmonic generation at 1064 nm is not significantly affected by lithium substitution in either of these phases. Crystal data: K{sub 0.55}Li{sub 0.45}TiOPO{sub 4}: M{sub r} = 183.55, orthorhombic, space group Pna2{sub 1} (No. 33), a = 12.741(2) {angstrom}, b = 6.357(1) {angstrom}, c = 10.535(2) {angstrom}, V = 853(2) {angstrom}{sup 3}, Z = 8, R(F) = 3.31% for 1393 reflections with I > 3{sigma}(I). K{sub 0.54}Li{sub 0.46}TiOAsO{sub 4}: M{sub r} = 227.11, orthorhombic, space group Pna2{sub 1} (No. 33), a = 13.018(2) {angstrom}, b = 6.589(1) {angstrom}, c = 10.766(2) {angstrom}, V = 923(2) {angstrom}{sup 3}, Z = 8, R(F) = 3.76% for 1637 reflections [I > 3{sigma}(I)]. 31 refs., 6 figs., 7 tabs.

• Research Organization: Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 569164
• Journal Information: Chemistry of Materials, Vol. 9, Issue 5; Other Information: PBD: May 1997
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
CATIONS
CRYSTALS
HARMONIC GENERATION
ION EXCHANGE
OPTICAL PROPERTIES
CRYSTAL STRUCTURE
SYNTHESIS
POTASSIUM IONS
STRUCTURAL CHEMICAL ANALYSIS
POTASSIUM PHOSPHATES
ELECTRO-OPTICAL EFFECTS
ELECTRICAL PROPERTIES
LASER RADIATION
LASER MATERIALS
REFRACTIVE INDEX
CHEMICAL BONDS
BOND LENGTHS
BOND ANGLE
STRUCTURE-ACTIVITY RELATIONSHIPS
STRUCTURAL MODELS
LITHIUM IONS