X-Ray Diffraction and Vibrational Spectroscopic Characteristics of Hydroxylclinohumite from Ruby-Bearing Marbles (Luc Yen District, Vietnam)

Table 2

Crystal data, data-collection information, and refinement details.

Crystal data
Formula	(Mg8.95Ti0.05)(SiO4)4F1.03OH0.97
Molecular weight	624.41
Colour	Canary-yellow
Crystal system	Monoclinic
Space group, 𝑍	P21/b, 2
𝑎,𝑏,𝑐 (Å) at 153 K*	4.7401(9), 10.231(2), 13.644(3)
𝛼 (°) at 153 K	100.82(3)
𝑉 (Å^3)	649.9(2)
𝐹(000), 𝜌calc (g/cm^3)	620, 3.19
𝜇 (mm^−1)	1.1
Crystal dimension (mm)	0.10×0.09×0.07
Data Collection
Diffractometer	NONIUS KAPPA APEX II
𝜆(Mo𝐾𝛼) (Å), 𝑇 (K)	0.71069, 153
Crystal-detector dist. (mm)	33.2
Collection mode, 2𝜃max (°)	sphere, 54.2
Rotation axis, width (°)	𝜑, 𝜔, 1
Total no. of frames	288
Collect. time per degree (s)	17
ℎ, 𝑘, 𝑙 ranges	−6/5, −12/13, −15/17
Total reflections measured	3546
Unique reflections	1426 (𝑅int 2.16 %)
Refinement
Refinement method	Full-matrix least-squares on 𝐹^2
Weighting coefficients 𝑎, 𝑏^∗∗	0.0161, 0.3314
No. of refined parameters	150
𝑅1(𝐹), 𝑤𝑅2(𝐹^2)all	1.98%, 4.95%
“Observed” refls.	1354[𝐹𝑜>4𝜎(𝐹𝑜)]
Extinction coefficient	0.0563(18)
GooF	1.134
Δ𝜌min, Δ𝜌max (𝑒/Å^3)	−0.282, 0.391

𝑅_int=Σ[𝐹²_𝑜−𝐹²_𝑜(mean)]/Σ𝐹²_𝑜,𝑅1=Σ||𝐹_𝑜|−|𝐹_𝑐||/Σ|𝐹_𝑜|; 𝑤𝑅2={Σ[𝑤(𝐹²_𝑜−𝐹²_𝑐)²]/Σ[𝑤(𝐹²_𝑜)²]}^1/2.
∗unit cell parameters at 25°C are as follows: 𝑎=4.7479(9), 𝑏=10.2387(20), 𝑐=13.6480(27), and 𝛼=100.89(3)^∘.
^∗∗𝑤=1/[𝜎²(𝐹²_𝑜)+(𝑎𝑃)²+𝑏𝑃], where 𝑃=(max(𝐹²_𝑜,0)+2𝐹_𝑐2)/3.
GooF={Σ[𝑤(𝐹²_𝑜−𝐹²_𝑐)²]/(𝑛−𝑝)}^1/2, where 𝑛 is number of reflections and 𝑝 is number of refined parameters.