Lithium diaqua­nickel(II) catena-borodiphosphate(V) monohydrate

Zheng, J.; Zhang, A.

doi:10.1107/S1600536809014652

inorganic compounds

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Volume 65| Part 6| June 2009| Page i42

doi:10.1107/S1600536809014652

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Lithium diaquanickel(II) catena-borodiphosphate(V) monohydrate

Juan Zheng ^a and Aiyun Zhang ^a ^*

^aDepartment of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454000, People's Republic of China
^*Correspondence e-mail: zay@hpu.edu.cn

(Received 22 March 2009; accepted 20 April 2009; online 7 May 2009)

The title borophosphate LiNi(H₂O)₂[BP₂O₈]·H₂O was synthesized under hydrothermal conditions. The crystal structure is isotypic with the Mg analogue and features helical [BP₂O₈]³⁻ borophosphate ribbons, constructed by BO₄ (2 symmetry) and PO₄ tetrahedra. The borate groups share all their oxygen apices with adjacent phosphate tetrahedra. The ribbons are connected via Ni²⁺ cations that are located on twofold rotation axes. The cations have a slightly distorted octahedral oxygen coordination by four O atoms from the anion and by two water molecules. The voids within the helices are occupied by Li⁺ cations, likewise located on twofold rotation axes, in an irregular environment of five O atoms. The structure is stabilized by O—H⋯O hydrogen bonds between coordinated or uncoordinated water molecules and O atoms that are part of the helices.

Related literature

For the isotypic Mg analogue, see: Lin et al. (2008 ). For other borophosphates, see: Boy & Kniep (2001 ); Kniep et al. (1998 ). A review on the structural chemistry of borophosphates is given by Ewald et al. (2007 ).

Experimental

Crystal data

LiNi(H₂O)₂[BP₂O₈]·H₂O
M_r = 320.44
Hexagonal, P 6₅ 22
a = 9.3359 (3) Å
c = 15.7497 (11) Å
V = 1188.82 (10) Å³
Z = 6
Mo Kα radiation
μ = 2.91 mm⁻¹
T = 296 K
0.22 × 0.20 × 0.17 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.567, T_max = 0.638
6139 measured reflections
708 independent reflections
684 reflections with I > 2σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.026
wR(F²) = 0.065
S = 1.14
708 reflections
75 parameters
H-atom parameters constrained
Δρ_max = 0.68 e Å⁻³
Δρ_min = −0.39 e Å⁻³
Absolute structure: Flack (1983 ), 235 Friedel pairs
Flack parameter: 0.01 (3)

Table 1
Selected bond lengths (Å)

Ni1—O1ⁱ	2.048 (3)
Ni1—O2	2.070 (3)
Ni1—O3	2.130 (3)
P2—O1	1.503 (3)
P2—O2	1.510 (3)
P2—O4	1.546 (3)
P2—O5	1.556 (3)
O6—Li	2.12 (2)
B—O5ⁱⁱ	1.461 (5)
B—O4ⁱⁱⁱ	1.471 (5)
Li—O2^iv	2.113 (13)
Li—O3^v	2.164 (4)
Symmetry codes: (i) $[-x+1, -x+y+1, -z+{\script{1\over 3}}]$ ; (ii) $[x, x-y, -z+{\script{5\over 6}}]$ ; (iii) $[y, x, -z+{\script{2\over 3}}]$ ; (iv) $[-y+1, x-y, z-{\script{1\over 3}}]$ ; (v) $[x, x-y, -z-{\script{1\over 6}}]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O5^iv	0.81	2.01	2.746 (4)	151
O3—H3A⋯O2^iv	0.81	2.60	3.165 (4)	128
O6—H6⋯O4^vi	0.83	2.52	3.331 (4)	167
O6—H6⋯O1^vi	0.83	2.66	3.092 (4)	114
O3—H3B⋯O1	0.83	2.00	2.810 (4)	167
O3—H3B⋯O2	0.83	2.54	2.955 (4)	112
Symmetry codes: (iv) $[-y+1, x-y, z-{\script{1\over 3}}]$ ; (vi) x-y, -y, -z.

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809014652/wm2227sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809014652/wm2227Isup2.hkl

checkCIF report

Comment top

With increasing interest in microporous materials, the synthesis of compounds like borophosphates with open framework structures have drawn much attention during the past few years. These compounds show a rich crystal chemistry (Kniep et al., 1998; Ewald et al., 2007).

The crystal structure of LiNi(H₂O)₂[BP₂O₈]_^.H₂O is isotypic with that of the Mg analogue (Lin et al. 2008) and contains an infinite one-dimensional anionic structure. The condensation of BO₄ and PO₄ tetrahedra leads to helical ribbons with composition [BP₂O₈]^3- (Fig. 1), whereby each BO₄ tetrahedron shares its vertices with four PO₄ tetrahedra. Bond lenghts and angles within the anionic structure are consistent with related borophosphates (Boy & Kniep, 2001; Lin et al., 2008).

The free loop of the borophosphate helix is occupied by Li⁺ cations, which are coordinated by with five O atoms, two from phosphate groups (O2) and three from water molecules (O3), thus completing an helical unit {Li[BP₂O₈]^2-} with a central channel running along the 6₅ screw axis. The channels are filled up with water of crystallization (O6). The Ni²⁺ cations, located on a twofold rotation axis, are surrounded in a distorted octahedral coordination by four O atoms from adjacent phosphate groups and two water molecules, leading to the overall formula LiNi(H₂O)₂[BP₂O₈]_^.H₂O (Fig. 2). The Ni—O distances range from 2.048 (3)–2.130 (3) Å and are in the usual range. The crystal structure is stabilized by O—H···O hydrogen bonds between coordinated or uncoordinated water molecules and O atoms that are part of the helices.

Related literature top

For the isotypic Mg analogue, see: Lin et al. (2008). For other borophosphates, see: Boy & Kniep (2001); Kniep et al. (1998). A review on the structural chemistry of borphosphates is given by Ewald et al. (2007).

Experimental top

Green block-shaped crystals were synthesized hydrothermally from a mixture of Ni(NO₃)₂, Li₂B₄O₇, water and H₃PO₄. In a typical synthesis, 0.87 g Ni(NO₃)_2^.6H₂O was dissolved in a mixture of 5 mL water, 1.691 g Li₂B₄O₇ and 2 ml H₃PO₄ (85%_wt ) under constant stirring. Finally, the mixture was kept in a 30 ml Teflon-lined steel autoclave at 443 K for 6d. The autoclave was slowly cooled to room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. A part of the structure of LiNi(H₂O)₂[BP₂O₈]_^.H₂O with displacement ellipsoids drawn at the 50% the probability level. Symmetry codes: (i) 1 - y, 1 - x, 0.16667 - z; (ii) 1 - x, 1 - x + y, 0.33333 - z; (iii) x-y, x, -0.16667 + z; (iv) y, x, 0.66667 - z; (v) y, -x + y, 0.16667 + z; (vi) x, x-y, 0.83333 - z.
	Fig. 2. Polyhedral diagram for LiNi(H₂O)₂[BP₂O₈]_^.H₂O in projection along [001]. Colour code: purple P, orange B, blue Ni, red OW6 and green Li.

Lithium diaquanickel(II) catena-borodiphosphate(V) monohydrate top

Crystal data top

LiNi(H₂O)₂[BP₂O₈]·H₂O	D_x = 2.686 Mg m⁻³
M_r = 320.44	Mo Kα radiation, λ = 0.71073 Å
Hexagonal, P6₅22	Cell parameters from 1684 reflections
Hall symbol: P 65 2 ( 0	θ = 2.5–29.5°
a = 9.3359 (3) Å	µ = 2.91 mm⁻¹
c = 15.7497 (11) Å	T = 296 K
V = 1188.82 (10) Å³	Block, green
Z = 6	0.22 × 0.20 × 0.17 mm
F(000) = 960

Data collection top

Bruker APEXII CCD area-detector diffractometer	708 independent reflections
Radiation source: fine-focus sealed tube	684 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.049
ϕ and ω scans	θ_max = 29.5°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −10→11
T_min = 0.567, T_max = 0.638	k = −8→11
6139 measured reflections	l = −18→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.026	H-atom parameters constrained
wR(F²) = 0.065	w = 1/[σ²(F_o²) + (0.0284P)² + 2.1868P] where P = (F_o² + 2F_c²)/3
S = 1.14	(Δ/σ)_max = 0.001
708 reflections	Δρ_max = 0.68 e Å⁻³
75 parameters	Δρ_min = −0.39 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 235 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.01 (3)

Crystal data top

LiNi(H₂O)₂[BP₂O₈]·H₂O	Z = 6
M_r = 320.44	Mo Kα radiation
Hexagonal, P6₅22	µ = 2.91 mm⁻¹
a = 9.3359 (3) Å	T = 296 K
c = 15.7497 (11) Å	0.22 × 0.20 × 0.17 mm
V = 1188.82 (10) Å³

Data collection top

Bruker APEXII CCD area-detector diffractometer	708 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	684 reflections with I > 2σ(I)
T_min = 0.567, T_max = 0.638	R_int = 0.049
6139 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.026	H-atom parameters constrained
wR(F²) = 0.065	Δρ_max = 0.68 e Å⁻³
S = 1.14	Δρ_min = −0.39 e Å⁻³
708 reflections	Absolute structure: Flack (1983), 235 Friedel pairs
75 parameters	Absolute structure parameter: 0.01 (3)
0 restraints

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R– factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Ni1	0.55533 (4)	0.44467 (4)	0.0833	0.0098 (2)
P2	0.38859 (12)	0.21675 (12)	0.24795 (7)	0.0093 (3)
O5	0.4156 (3)	0.2355 (3)	0.34570 (16)	0.0108 (6)
O4	0.2137 (3)	0.1899 (4)	0.23106 (18)	0.0129 (7)
O3	0.4865 (4)	0.1970 (4)	0.05090 (19)	0.0214 (7)
O2	0.5200 (4)	0.3782 (3)	0.21028 (17)	0.0142 (7)
O1	0.3853 (4)	0.0644 (4)	0.21452 (17)	0.0151 (7)
O6	0.2044 (10)	0.1022 (5)	−0.0833	0.079 (2)
B	0.3037 (8)	0.1518 (4)	0.4167	0.0090 (13)
Li	0.466 (3)	0.2331 (13)	−0.0833	0.080 (5)
H3A	0.5738	0.2196	0.0284	0.096*
H6	0.1509	0.0382	−0.1223	0.096*
H3B	0.4428	0.1571	0.0973	0.096*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.0098 (3)	0.0098 (3)	0.0100 (3)	0.0050 (3)	0.0013 (3)	0.0013 (3)
P2	0.0097 (5)	0.0097 (5)	0.0086 (5)	0.0050 (4)	0.0015 (4)	0.0015 (4)
O5	0.0095 (14)	0.0126 (16)	0.0089 (13)	0.0044 (12)	0.0014 (11)	0.0016 (11)
O4	0.0131 (16)	0.0132 (15)	0.0157 (16)	0.0091 (13)	−0.0022 (12)	−0.0030 (12)
O3	0.0277 (18)	0.0162 (18)	0.0231 (17)	0.0130 (14)	0.0121 (14)	0.0049 (14)
O2	0.0143 (16)	0.0134 (14)	0.0101 (13)	0.0032 (13)	0.0021 (12)	0.0040 (11)
O1	0.0211 (17)	0.0159 (16)	0.0147 (14)	0.0140 (14)	0.0008 (14)	−0.0017 (12)
O6	0.083 (6)	0.061 (3)	0.100 (6)	0.042 (3)	0.000	−0.024 (4)
B	0.012 (3)	0.009 (2)	0.007 (3)	0.0059 (15)	0.000	0.001 (2)
Li	0.094 (15)	0.089 (10)	0.058 (10)	0.047 (8)	0.000	0.011 (10)

Geometric parameters (Å, º) top

Ni1—O1ⁱ	2.048 (3)	O4—Bⁱ	1.471 (5)
Ni1—O1ⁱⁱ	2.048 (3)	O3—Li	2.164 (4)
Ni1—O2ⁱⁱⁱ	2.070 (3)	O2—Li^iv	2.113 (13)
Ni1—O2	2.070 (3)	O1—Ni1^v	2.048 (3)
Ni1—O3	2.130 (3)	O6—Li	2.12 (2)
Ni1—O3ⁱⁱⁱ	2.130 (3)	B—O5^vi	1.461 (5)
Ni1—Li	3.137 (5)	B—O4^vii	1.471 (5)
Ni1—Li^iv	3.137 (5)	B—O4^v	1.471 (5)
P2—O1	1.503 (3)	Li—O2ⁱⁱⁱ	2.113 (13)
P2—O2	1.510 (3)	Li—O2^viii	2.113 (13)
P2—O4	1.546 (3)	Li—O3^ix	2.164 (4)
P2—O5	1.556 (3)	Li—Ni1^viii	3.137 (5)
O5—B	1.461 (5)

O1ⁱ—Ni1—O1ⁱⁱ	92.58 (18)	B—O5—P2	131.6 (3)
O1ⁱ—Ni1—O2ⁱⁱⁱ	88.53 (11)	Bⁱ—O4—P2	127.8 (3)
O1ⁱⁱ—Ni1—O2ⁱⁱⁱ	101.19 (12)	Ni1—O3—Li	93.87 (18)
O1ⁱ—Ni1—O2	101.19 (12)	P2—O2—Ni1	127.36 (17)
O1ⁱⁱ—Ni1—O2	88.53 (11)	P2—O2—Li^iv	129.2 (4)
O2ⁱⁱⁱ—Ni1—O2	166.00 (17)	Ni1—O2—Li^iv	97.1 (2)
O1ⁱ—Ni1—O3	86.52 (13)	P2—O1—Ni1^v	140.72 (18)
O1ⁱⁱ—Ni1—O3	177.55 (12)	O5^vi—B—O5	103.4 (4)
O2ⁱⁱⁱ—Ni1—O3	81.08 (11)	O5^vi—B—O4^vii	111.43 (15)
O2—Ni1—O3	89.40 (11)	O5—B—O4^vii	114.16 (15)
O1ⁱ—Ni1—O3ⁱⁱⁱ	177.55 (12)	O5^vi—B—O4^v	114.16 (15)
O1ⁱⁱ—Ni1—O3ⁱⁱⁱ	86.52 (13)	O5—B—O4^v	111.43 (16)
O2ⁱⁱⁱ—Ni1—O3ⁱⁱⁱ	89.40 (11)	O4^vii—B—O4^v	102.6 (4)
O2—Ni1—O3ⁱⁱⁱ	81.08 (11)	O2ⁱⁱⁱ—Li—O2^viii	106.9 (9)
O3—Ni1—O3ⁱⁱⁱ	94.47 (19)	O2ⁱⁱⁱ—Li—O6	126.5 (5)
O1ⁱ—Ni1—Li	72.0 (4)	O2^viii—Li—O6	126.5 (5)
O1ⁱⁱ—Ni1—Li	138.23 (8)	O2ⁱⁱⁱ—Li—O3	79.3 (3)
O2ⁱⁱⁱ—Ni1—Li	41.9 (3)	O2^viii—Li—O3	95.5 (4)
O2—Ni1—Li	131.83 (17)	O6—Li—O3	94.3 (6)
O3—Ni1—Li	43.50 (9)	O2ⁱⁱⁱ—Li—O3^ix	95.5 (4)
O3ⁱⁱⁱ—Ni1—Li	107.3 (4)	O2^viii—Li—O3^ix	79.3 (3)
O1ⁱ—Ni1—Li^iv	138.23 (8)	O6—Li—O3^ix	94.3 (6)
O1ⁱⁱ—Ni1—Li^iv	72.0 (4)	O3—Li—O3^ix	171.3 (11)
O2ⁱⁱⁱ—Ni1—Li^iv	131.83 (17)	O2ⁱⁱⁱ—Li—Ni1	40.91 (9)
O2—Ni1—Li^iv	41.9 (3)	O2^viii—Li—Ni1	118.8 (6)
O3—Ni1—Li^iv	107.3 (4)	O6—Li—Ni1	103.3 (4)
O3ⁱⁱⁱ—Ni1—Li^iv	43.50 (9)	O3—Li—Ni1	42.64 (13)
Li—Ni1—Li^iv	143.2 (5)	O3^ix—Li—Ni1	134.5 (3)
O1—P2—O2	115.38 (17)	O2ⁱⁱⁱ—Li—Ni1^viii	118.8 (6)
O1—P2—O4	105.45 (17)	O2^viii—Li—Ni1^viii	40.91 (9)
O2—P2—O4	111.07 (18)	O6—Li—Ni1^viii	103.3 (4)
O1—P2—O5	112.24 (16)	O3—Li—Ni1^viii	134.5 (4)
O2—P2—O5	105.75 (16)	O3^ix—Li—Ni1^viii	42.64 (13)
O4—P2—O5	106.70 (15)	Ni1—Li—Ni1^viii	153.4 (7)

Symmetry codes: (i) x−y, x, z−1/6; (ii) −x+1, −x+y+1, −z+1/3; (iii) −y+1, −x+1, −z+1/6; (iv) −x+y+1, −x+1, z+1/3; (v) y, −x+y, z+1/6; (vi) x, x−y, −z+5/6; (vii) y, x, −z+2/3; (viii) −y+1, x−y, z−1/3; (ix) x, x−y, −z−1/6.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O5^viii	0.81	2.01	2.746 (4)	151
O3—H3A···O2^viii	0.81	2.60	3.165 (4)	128
O6—H6···O4^x	0.83	2.52	3.331 (4)	167
O6—H6···O1^x	0.83	2.66	3.092 (4)	114
O3—H3B···O1	0.83	2.00	2.810 (4)	167
O3—H3B···O2	0.83	2.54	2.955 (4)	112

Symmetry codes: (viii) −y+1, x−y, z−1/3; (x) x−y, −y, −z.

Experimental details

Crystal data
Chemical formula	LiNi(H₂O)₂[BP₂O₈]·H₂O
M_r	320.44
Crystal system, space group	Hexagonal, P6₅22
Temperature (K)	296
a, c (Å)	9.3359 (3), 15.7497 (11)
V (Å³)	1188.82 (10)
Z	6
Radiation type	Mo Kα
µ (mm⁻¹)	2.91
Crystal size (mm)	0.22 × 0.20 × 0.17

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.567, 0.638
No. of measured, independent and observed [I > 2σ(I)] reflections	6139, 708, 684
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.692

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.026, 0.065, 1.14
No. of reflections	708
No. of parameters	75
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.68, −0.39
Absolute structure	Flack (1983), 235 Friedel pairs
Absolute structure parameter	0.01 (3)

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Ni1—O1ⁱ	2.048 (3)	P2—O5	1.556 (3)
Ni1—O2	2.070 (3)	O6—Li	2.12 (2)
Ni1—O3	2.130 (3)	B—O5ⁱⁱ	1.461 (5)
P2—O1	1.503 (3)	B—O4ⁱⁱⁱ	1.471 (5)
P2—O2	1.510 (3)	Li—O2^iv	2.113 (13)
P2—O4	1.546 (3)	Li—O3^v	2.164 (4)

Symmetry codes: (i) −x+1, −x+y+1, −z+1/3; (ii) x, x−y, −z+5/6; (iii) y, x, −z+2/3; (iv) −y+1, x−y, z−1/3; (v) x, x−y, −z−1/6.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O5^iv	0.81	2.01	2.746 (4)	150.7
O3—H3A···O2^iv	0.81	2.60	3.165 (4)	128.2
O6—H6···O4^vi	0.83	2.52	3.331 (4)	166.7
O6—H6···O1^vi	0.83	2.66	3.092 (4)	114.3
O3—H3B···O1	0.83	2.00	2.810 (4)	167.3
O3—H3B···O2	0.83	2.54	2.955 (4)	112.1

Symmetry codes: (iv) −y+1, x−y, z−1/3; (vi) x−y, −y, −z.

Acknowledgements

This work was supported by the Main Teacher Project of Hena Province (grant No. 649082) and the Foundation of Graduate Produce (reference 2008-M-17).

References

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