Nicolás Flores-González, Javier Castells-Gil, Bo Dong, Wilgner Lima da Silva, Alex J. Green, Shilpi Sengupta, Peter J. Baker, Ivan da Silva, Duncan H. Gregory, Peter Slater. “Li⁺ dynamics in LiTa₂PO₈ probed by μ⁺SR.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007619/v2

The plotted diffraction, Raman, diffuse-reflectance UV–Vis and μ⁺SR data in the main paper, pp. 10, 14, 16, 18, and SI, pp. 2–4, 6–7, were not transcribed

LiTa₂PO₈
Powder neutron diffraction Li₃PO₄ impurity <1 wt. %
Powder neutron diffraction, Rietveld refinement Monoclinic, space group C2/c; a = 9.7142(1) Å, b = 11.5329(1) Å, c = 10.6969(1) Å, β = 90.012(1)°, V = 1198.41(2) ų; overall Rwp = 2.27 %; GOF = 1.22
Powder neutron diffraction, Rietveld-refined atomic parameters; x, y, z; S.O.F.; Biso (Ų) Ta1 (8f): 0.2462(1), 0.0955(1), 0.2546(2); 1; 0.30(2). Ta2 (4e): 0, 0.3465(1), 0.25; 1; 0.44(2). Ta3 (4a): 0, 0, 0; 1; 0.47(2). P1 (8f): 0.4976(3), 0.2083(2), 0.0601(2); 1; 0.51(1). O1 (8f): 0.4432(2), 0.1660(2), -0.0675(2); 1; 0.87(1). O2 (8f): 0.5440(2), 0.33688(2), 0.0501(2); 1; 0.87(1). O3 (8f): 0.3789(2), 0.2012(2), 0.1520(2); 1; 0.87(1). O4 (8f): 0.619(2), 0.1373(1), 0.096(1); 1; 0.87(1). O5 (8f): 0.359(1), 0.511(1), 0.1291(9); 1; 1.10(1). O6 (8f): 0.141(1), 0.2363(2), 0.2879(2); 1; 1.10(1). O7 (8f): 0.1365(6), 0.0571(2), 0.1126(2); 1; 1.10(1). O8 (8f): 0.1322(3), 0.4672(2), 0.2828(2); 1; 1.10(1). Li1 (8f): 0.755(1), 0.622(1), 0.571(1); 0.41(1); 6.7(3). Li2 (8f): 0.762(2), 0.849(2), 0.148(2); 0.59(1); 6.7(3)
Raman spectroscopy (room temperature, 633 nm) PO₄ internal stretching modes above 1000 cm⁻¹; TaO₆ internal stretching modes between 800 and 950 cm⁻¹; TaO₆ and PO₄ internal bending modes between 500 and 700 cm⁻¹; cage modes between 350 and 500 cm⁻¹; lattice modes below 350 cm⁻¹, assigned to O–Ta–O and O–Li–O vibrations with maxima at approximately 125 and 205 cm⁻¹, respectively
Diffuse-reflectance UV–Vis spectroscopy, Tauc analysis Direct optical band gap 4.26 eV; indirect optical band gap 4.20 eV
μ⁺SR, dynamic Gaussian Kubo–Toyabe fit at 50 K AKT = 0.22(1), ABG = 0.037(13), Aμ = 0.0329(1), Δ = 0.092(3), ν = 0.046(9), λ = 0.40(3)
μ⁺SR, muonium contribution Progressively decreased with increasing temperature and became negligible above 175 K
μ⁺SR, local-field distribution Between 75 and 250 K, the magnitude did not change significantly; Δ = 0.0936(9) MHz at 250 K
Transverse-field μ⁺SR, inverse correlation time and fluctuation rate (MHz) 175 K: 1/τc = 0.13(1), ν = 0.111(5); 200 K: 1/τc = 0.21(2), ν = 0.195(7); 230 K: 1/τc = 0.26(2), ν = 0.259(9); 250 K: 1/τc = 0.36(3), ν = 0.31(1)
μ⁺SR fluctuation rate, Arrhenius fit Activation energy 0.113(10) eV from approximately 150 to 210 K; activation energy 0.300(25) eV from 210 to 290 K