The crystal structures of ammonium tetraphenylborate, NH
4+·BPh
4−, are determined by neutron diffraction at 20 and 293 K. At both temperatures, all four N—H vectors of the ammonium ion are time-average-oriented at the midpoints of the phenyl rings of neighboring anions. The N—H
Ph distances, H
M 2.067 and N
M 3.023 Å, are exceptionally short (
M = aromatic midpoint). Even at 20 K the ammonium ion performs large amplitude motions which allow the N—H vectors to sample the entire face of the aromatic system.
Supporting information
CCDC references: 144361; 144362
For both compounds, program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997).
(lt) ammonium tetraphenylborate
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Crystal data top
NH4+·C24H20B− | Dx = 1.132 Mg m−3 |
Mr = 337.27 | Neutron radiation, λ = 0.8469 Å |
Tetragonal, I42m | Cell parameters from 354 reflections |
a = 11.1208 (8) Å | θ = 3.1–44.4° |
c = 8.0033 (7) Å | µ = 0.06 mm−1 |
V = 989.79 (13) Å3 | T = 20 K |
Z = 2 | Block, colorless transparent |
F(000) = 360 | 1.72 × 1.00 × 0.83 mm |
Data collection top
D9 diffractometer | Rint = 0.030 |
Radiation source: ILL high flux neutron reactor | θmax = 45.1°, θmin = 3.1° |
area detector scans | h = −10→18 |
Absorption correction: gaussian | k = −6→18 |
Tmin = 0.761, Tmax = 0.826 | l = 0→13 |
1278 measured reflections | 3 standard reflections every 50 reflections |
736 independent reflections | intensity decay: none |
639 reflections with I > 2σ(I) | |
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)] = 0.038 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.066 | w = 1/[σ2(Fo2) + 5.0563P] where P = (Fo2 + 2Fc2)/3 |
S = 1.10 | (Δ/σ)max < 0.001 |
736 reflections | Δρmax = 1.38 e Å−3 |
65 parameters | Δρmin = −1.14 e Å−3 |
0 restraints | Absolute structure: Flack H D (1983), Acta Cryst. A39, 876-881 |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.0 (2) |
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 | Uiso*/Ueq | |
B | 0.0000 | 0.0000 | 0.0000 | 0.0034 (5) | |
N | 0.0000 | 0.0000 | 0.5000 | 0.0080 (3) | |
C1 | 0.08200 (9) | 0.08200 (9) | 0.12672 (18) | 0.0048 (2) | |
C2 | 0.04000 (9) | 0.19147 (9) | 0.19306 (14) | 0.00640 (16) | |
C3 | 0.10202 (9) | 0.25438 (9) | 0.31756 (14) | 0.00746 (17) | |
C4 | 0.20961 (10) | 0.20961 (10) | 0.38113 (19) | 0.0079 (2) | |
H2 | −0.0455 (2) | 0.2280 (2) | 0.1484 (3) | 0.0209 (5) | |
H3 | 0.0649 (3) | 0.3379 (2) | 0.3653 (4) | 0.0239 (5) | |
H4 | 0.2569 (3) | 0.2569 (3) | 0.4807 (5) | 0.0228 (7) | |
H5 | 0.0491 (5) | 0.0491 (5) | 0.4288 (12) | 0.092 (4) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
B | 0.0033 (7) | 0.0033 (7) | 0.0036 (12) | 0.000 | 0.000 | 0.000 |
N | 0.0085 (5) | 0.0085 (5) | 0.0070 (8) | 0.000 | 0.000 | 0.000 |
C1 | 0.0050 (3) | 0.0050 (3) | 0.0044 (5) | 0.0004 (4) | −0.0008 (3) | −0.0008 (3) |
C2 | 0.0069 (3) | 0.0055 (4) | 0.0067 (3) | 0.0002 (3) | −0.0007 (3) | −0.0017 (4) |
C3 | 0.0085 (4) | 0.0064 (4) | 0.0074 (4) | 0.0000 (3) | −0.0003 (4) | −0.0018 (3) |
C4 | 0.0082 (3) | 0.0082 (3) | 0.0073 (5) | −0.0010 (5) | −0.0016 (4) | −0.0016 (4) |
H2 | 0.0149 (9) | 0.0235 (11) | 0.0243 (11) | 0.0074 (8) | −0.0058 (9) | −0.0055 (9) |
H3 | 0.0270 (12) | 0.0175 (10) | 0.0274 (11) | 0.0062 (9) | −0.0025 (11) | −0.0096 (9) |
H4 | 0.0233 (9) | 0.0233 (9) | 0.0217 (16) | −0.0011 (13) | −0.0079 (10) | −0.0079 (10) |
H5 | 0.104 (5) | 0.104 (5) | 0.069 (5) | −0.059 (6) | 0.029 (3) | 0.029 (3) |
Geometric parameters (Å, º) top
B—C1i | 1.6406 (14) | C2—C3 | 1.3993 (14) |
B—C1ii | 1.6406 (14) | C2—H2 | 1.095 (3) |
B—C1iii | 1.6406 (14) | C3—C4 | 1.3922 (13) |
B—C1 | 1.6407 (14) | C3—H3 | 1.086 (3) |
N—H5 | 0.960 (7) | C4—C3iv | 1.3922 (13) |
C1—C2 | 1.4078 (13) | C4—H4 | 1.089 (4) |
C1—C2iv | 1.4078 (13) | | |
| | | |
C1i—B—C1ii | 103.64 (10) | C3—C2—C1 | 122.50 (10) |
C1i—B—C1iii | 112.46 (5) | C3—C2—H2 | 118.37 (17) |
C1ii—B—C1iii | 112.46 (5) | C1—C2—H2 | 119.11 (17) |
C1i—B—C1 | 112.46 (5) | C4—C3—C2 | 120.34 (11) |
C1ii—B—C1 | 112.46 (5) | C4—C3—H3 | 120.28 (19) |
C1iii—B—C1 | 103.64 (10) | C2—C3—H3 | 119.38 (18) |
C2—C1—C2iv | 115.56 (13) | C3—C4—C3iv | 118.76 (14) |
C2—C1—B | 121.96 (6) | C3—C4—H4 | 120.62 (7) |
C2iv—C1—B | 121.96 (6) | C3iv—C4—H4 | 120.62 (7) |
| | | |
C1i—B—C1—C2 | 36.02 (9) | C1iii—B—C1—C2iv | 85.70 (11) |
C1ii—B—C1—C2 | 152.58 (14) | C2iv—C1—C2—C3 | −0.4 (2) |
C1iii—B—C1—C2 | −85.70 (11) | B—C1—C2—C3 | 171.48 (10) |
C1i—B—C1—C2iv | −152.57 (14) | C1—C2—C3—C4 | −0.03 (17) |
C1ii—B—C1—C2iv | −36.02 (9) | C2—C3—C4—C3iv | 0.5 (2) |
Symmetry codes: (i) −y, x, −z; (ii) y, −x, −z; (iii) −x, −y, z; (iv) y, x, z. |
(rt) ammonium tetraphenylborate
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Crystal data top
NH4+·C24H20B− | Dx = 1.101 Mg m−3 |
Mr = 337.27 | Neutron radiation, λ = 0.8469 Å |
Tetragonal, I42m | Cell parameters from 124 reflections |
a = 11.2255 (15) Å | θ = 3.1–25.6° |
c = 8.0745 (13) Å | µ = 0.06 mm−1 |
V = 1017.5 (3) Å3 | T = 293 K |
Z = 2 | Block, colorless transparent |
F(000) = 360 | 1.72 × 1.00 × 0.83 mm |
Data collection top
D9 diffractometer | Rint = 0.039 |
Radiation source: ILL high flux neutron reactor | θmax = 34.8°, θmin = 3.0° |
area detector scans | h = −10→15 |
Absorption correction: gaussian | k = −6→15 |
Tmin = 0.777, Tmax = 0.826 | l = 0→10 |
662 measured reflections | 3 standard reflections every 50 reflections |
418 independent reflections | intensity decay: none |
364 reflections with I > 2σ(I) | |
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)] = 0.069 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.116 | w = 1/[σ2(Fo2) + 7.8251P] where P = (Fo2 + 2Fc2)/3 |
S = 1.23 | (Δ/σ)max < 0.001 |
418 reflections | Δρmax = 0.64 e Å−3 |
65 parameters | Δρmin = −0.57 e Å−3 |
0 restraints | Absolute structure: Flack H D (1983), Acta Cryst. A39, 876-881 |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.4 (4) |
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 | Uiso*/Ueq | |
B | 0.0000 | 0.0000 | 0.0000 | 0.0211 (17) | |
N | 0.0000 | 0.0000 | 0.5000 | 0.0421 (16) | |
C1 | 0.0811 (2) | 0.0811 (2) | 0.1255 (5) | 0.0255 (8) | |
C2 | 0.0399 (3) | 0.1897 (3) | 0.1917 (4) | 0.0359 (7) | |
C3 | 0.1009 (4) | 0.2518 (3) | 0.3156 (5) | 0.0459 (9) | |
C4 | 0.2077 (3) | 0.2077 (3) | 0.3782 (8) | 0.0535 (14) | |
H2 | −0.0444 (8) | 0.2267 (7) | 0.1447 (12) | 0.063 (2) | |
H3 | 0.0670 (10) | 0.3354 (9) | 0.3603 (13) | 0.081 (3) | |
H4 | 0.2557 (11) | 0.2557 (11) | 0.4756 (17) | 0.091 (5) | |
H5 | 0.0456 (17) | 0.0456 (17) | 0.437 (3) | 0.162 (12) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
B | 0.017 (2) | 0.017 (2) | 0.028 (5) | 0.000 | 0.000 | 0.000 |
N | 0.049 (3) | 0.049 (3) | 0.027 (4) | 0.000 | 0.000 | 0.000 |
C1 | 0.0269 (11) | 0.0269 (11) | 0.0226 (15) | −0.0040 (14) | 0.0007 (11) | 0.0007 (11) |
C2 | 0.0427 (16) | 0.0307 (15) | 0.0344 (13) | −0.0021 (11) | 0.0002 (15) | −0.0093 (14) |
C3 | 0.060 (2) | 0.0385 (17) | 0.0393 (17) | −0.0135 (15) | −0.0004 (19) | −0.0108 (16) |
C4 | 0.057 (2) | 0.057 (2) | 0.047 (3) | −0.027 (3) | −0.0068 (18) | −0.0068 (18) |
H2 | 0.064 (5) | 0.051 (4) | 0.075 (5) | 0.011 (3) | −0.004 (5) | −0.016 (4) |
H3 | 0.091 (7) | 0.065 (5) | 0.087 (7) | 0.002 (5) | −0.011 (6) | −0.027 (5) |
H4 | 0.105 (7) | 0.105 (7) | 0.062 (8) | −0.043 (9) | −0.022 (5) | −0.022 (5) |
H5 | 0.167 (16) | 0.167 (16) | 0.15 (2) | −0.026 (17) | 0.060 (12) | 0.060 (12) |
Geometric parameters (Å, º) top
B—C1 | 1.638 (4) | C2—C3 | 1.398 (5) |
B—C1i | 1.638 (4) | C2—H2 | 1.101 (9) |
B—C1ii | 1.638 (4) | C3—C4 | 1.393 (5) |
B—C1iii | 1.638 (4) | C3—H3 | 1.074 (10) |
N—H5 | 0.89 (2) | C4—C3iv | 1.393 (5) |
C1—C2 | 1.409 (4) | C4—H4 | 1.095 (14) |
C1—C2iv | 1.409 (4) | | |
| | | |
C1—B—C1i | 112.49 (14) | C3—C2—C1 | 122.9 (4) |
C1—B—C1ii | 112.49 (14) | C3—C2—H2 | 118.6 (5) |
C1i—B—C1ii | 103.6 (3) | C1—C2—H2 | 118.5 (5) |
C1—B—C1iii | 103.6 (3) | C4—C3—C2 | 120.2 (4) |
C1i—B—C1iii | 112.49 (14) | C4—C3—H3 | 119.5 (7) |
C1ii—B—C1iii | 112.49 (14) | C2—C3—H3 | 120.2 (7) |
C2—C1—C2iv | 115.1 (4) | C3iv—C4—C3 | 118.7 (5) |
C2—C1—B | 122.21 (19) | C3iv—C4—H4 | 120.6 (2) |
C2iv—C1—B | 122.21 (19) | C3—C4—H4 | 120.6 (2) |
Symmetry codes: (i) −y, x, −z; (ii) y, −x, −z; (iii) −x, −y, z; (iv) y, x, z. |