Buy article online - an online subscription or single-article purchase is required to access this article.
Download citation
Download citation
link to html
The structure of the title compound, [PbBr2(C3H7NO2)], contains Pb2+ ions, Br ions and β-alanine mol­ecules in their zwitterion form. Each lead(II) ion has a seven-coordinate geometry, with four sites occupied by Br ions, two by a bidentate carboxyl­ate group and the last by a single O atom. The singly-bridging Br ions link the PbII ions into layers that are further aggregated into a three dimensional array by the formation of Pb—O bonds and hydrogen bonds involving the —NH3+ groups.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803011619/na6234sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536803011619/na6234Isup2.hkl
Contains datablock I

CCDC reference: 217351

Key indicators

  • Single-crystal X-ray study
  • T = 82 K
  • Mean [sigma](C-C) = 0.008 Å
  • R factor = 0.018
  • wR factor = 0.042
  • Data-to-parameter ratio = 16.9

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry








Comment top

The sevenfold local coordination for the lead(II) ion is shown in Fig. 1, and can conveniently be viewed as a severely distorted octahedron in which one site of the octahedron is occupied by the bidentate carboxylate group. The four Pb—Br bonds range from 2.9918 (6) to 3.1731 (5) Å. The carboxylate group in the zwitterion form of the β-alanine molecule coordinates in one octahedral site in a bidentate fashion, while the sixth site is occupied by an O atom from a β-alanine molecule of an adjacent octahedron. The Pb—O distances are 2.533 (3) and 2.600 (4) Å for the O atoms in the bidentate group, and 2.754 (4) Å for the bridging O atom. As anticipated, the angular distortions imposed by the presence of the bidentate group are significant. As is also seen in Fig. 1, the backbone of the β-alanine molecule assumes a gauche conformation. As discussed below, this allows the formation of an intramolecular hydrogen bond as well as several other interactions.

Corner-sharing through the bromide ions on adjacent octahedra lead to the formation of a two-dimensional structure, as shown in Fig. 2. This layer structure may be viewed as an (110) section of the parent cubic AMX3 structure. This is a single metal halide layer of the type in the multiple layer (NH2CINH2)2(CH3NH3)n-1SnnI3n+1 (110) sections reported by Mitzi et al. (1995). This is in contrast to the typical [001] section formed by the (RNH3)2MX4 layer perovskite compounds such as in the (β-alaninium)2CuX4 salts (X = Cl and Br) (Willett, et al., 1981, 1983).

These metal halide layers are linked together via bibridged Pb—O—Pb bonds (dashed lines, Fig. 3), as well as N—H···O and N—H···Br hydrogen bonds (dashed lines, inset, Fig. 3). These Pb—O bonds are 0.15 Å longer than those in the bidentate linkage. The bridging Pb—O—Pb angle is 109.0 (1)°. The –NH3+ group forms one asymmetric bifurcated hydrogen bond (to two different Br2, see Table 1) and two normal hydrogen bonds (to Br1 and O1). The intramolecular N—H···Br hydrogen bond is nearly 0.2 Å longer than the one between layers, presumably because of steric constraints on the conformation of the β-alanine molecule·In addition, there is an electrostatic interaction of the –NH3+ group with an O2 atom from the adjacent layer, in which the C—N···O angle is close to linear.

Experimental top

Crystals of the title compound were prepared by slow evaporation of a solution obtained by dissolving 0.9282 g PbBr2 (0.002 mmol) and 0.4550 g β-alanine (0.005 mmol) in 80 ml deionized water that had been acidified with 5 drops of concentrated HBr.

Refinement top

H atoms were positioned geometrically and refined using a riding model, with Uiso for the methylene C—H groups constrained to be 1.2Ueq of the carrier atom, while those of the N—H protons were set at 1.5Ueq. There is a large residual of 1.19 e Å −3 ca 0.92 Å from Pb1.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. Illustration of the lead(II) ion coordination. Ellipsoids are drawn at the 70% probability level.
[Figure 2] Fig. 2. Illustration of the [110] PbBr2 layer.
[Figure 3] Fig. 3. Illustration of the interconnection of the PbBr2 layers, as viewed down the a direction. The b axis is horizontal. The bridging Pb—O bonds are shown as dotted lines. The inset shows the hydrogen-bonding contacts.
Lead(II) bromide β-alanine top
Crystal data top
[PbBr2(C3H7NO2)]F(000) = 800
Mr = 456.11Dx = 3.737 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 6.0073 (4) Åθ = 2.5–28.3°
b = 16.5286 (10) ŵ = 30.60 mm1
c = 8.3057 (5) ÅT = 82 K
β = 100.56 (1)°Rhomboid, colorless
V = 810.71 (9) Å30.11 × 0.08 × 0.06 mm
Z = 4
Data collection top
Bruker–Siemens SMART APEX
diffractometer
1423 independent reflections
Radiation source: normal-focus sealed tube1366 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
Detector resolution: 8.3 pixels mm-1θmax = 25.0°, θmin = 2.5°
ω scansh = 77
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
k = 1919
Tmin = 0.066, Tmax = 0.159l = 99
7447 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.018H-atom parameters constrained
wR(F2) = 0.042 w = 1/[σ2(Fo2) + 2.9938P]
where P = (Fo2 + 2Fc2)/3
S = 1.20(Δ/σ)max = 0.001
1423 reflectionsΔρmax = 1.11 e Å3
84 parametersΔρmin = 0.68 e Å3
48 restraintsExtinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.00191 (12)
Crystal data top
[PbBr2(C3H7NO2)]V = 810.71 (9) Å3
Mr = 456.11Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.0073 (4) ŵ = 30.60 mm1
b = 16.5286 (10) ÅT = 82 K
c = 8.3057 (5) Å0.11 × 0.08 × 0.06 mm
β = 100.56 (1)°
Data collection top
Bruker–Siemens SMART APEX
diffractometer
1423 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
1366 reflections with I > 2σ(I)
Tmin = 0.066, Tmax = 0.159Rint = 0.034
7447 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.01848 restraints
wR(F2) = 0.042H-atom parameters constrained
S = 1.20Δρmax = 1.11 e Å3
1423 reflectionsΔρmin = 0.68 e Å3
84 parameters
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
xyzUiso*/Ueq
Pb10.04516 (3)0.383518 (12)0.12507 (2)0.00242 (10)
Br10.10815 (9)0.25372 (3)0.37005 (6)0.00587 (14)
Br20.45035 (8)0.40113 (3)0.12565 (6)0.00672 (13)
O10.1708 (6)0.4607 (2)0.3896 (4)0.0067 (8)
O20.0661 (6)0.5390 (2)0.1725 (4)0.0078 (8)
N10.6250 (8)0.6014 (3)0.2990 (5)0.0075 (10)
H1A0.69510.58120.39720.011*
H1B0.72330.63330.25640.011*
H1C0.57890.55980.22900.011*
C40.1616 (8)0.5292 (3)0.3197 (6)0.0019 (10)
C20.4228 (9)0.6506 (3)0.3225 (6)0.0062 (11)
H2A0.33580.66690.21430.007*
H2B0.47450.70040.38450.007*
C30.2715 (10)0.6027 (3)0.4143 (6)0.0057 (11)
H3A0.15090.63880.43960.007*
H3B0.36220.58420.51950.007*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Pb10.00103 (14)0.00296 (13)0.00330 (13)0.00016 (7)0.00051 (7)0.00020 (7)
Br10.0075 (3)0.0043 (3)0.0058 (3)0.0003 (2)0.00138 (19)0.0015 (2)
Br20.0019 (3)0.0115 (3)0.0069 (3)0.0003 (2)0.0013 (2)0.0006 (2)
O10.006 (2)0.009 (2)0.0037 (18)0.0021 (16)0.0003 (15)0.0016 (15)
O20.009 (2)0.007 (2)0.0062 (18)0.0014 (16)0.0018 (15)0.0002 (15)
N10.007 (3)0.011 (3)0.004 (2)0.0008 (19)0.0015 (18)0.0005 (18)
C40.0015 (13)0.0024 (13)0.0021 (13)0.0006 (9)0.0011 (9)0.0002 (9)
C20.0061 (14)0.0058 (14)0.0063 (13)0.0005 (9)0.0000 (9)0.0005 (9)
C30.0055 (14)0.0056 (14)0.0057 (13)0.0003 (9)0.0008 (9)0.0012 (9)
Geometric parameters (Å, º) top
Pb1—O12.533 (3)O2—Pb1i2.755 (4)
Pb1—O22.600 (4)N1—C21.505 (7)
Pb1—O2i2.755 (4)N1—H1A0.9100
Pb1—Br12.9333 (5)N1—H1B0.9100
Pb1—Br22.9918 (6)N1—H1C0.9100
Pb1—Br2ii3.0437 (6)C4—C31.530 (7)
Pb1—Br1iii3.1731 (5)C2—C31.513 (7)
Br1—Pb1iv3.1731 (5)C2—H2A0.9900
Br2—Pb1v3.0437 (6)C2—H2B0.9900
O1—C41.270 (6)C3—H3A0.9900
O2—C41.262 (6)C3—H3B0.9900
O1—Pb1—O251.12 (11)C4—O2—Pb191.2 (3)
O1—Pb1—O2i121.93 (12)C4—O2—Pb1i157.1 (3)
O2—Pb1—O2i70.95 (12)Pb1—O2—Pb1i109.05 (12)
O1—Pb1—Br177.67 (8)C2—N1—H1A109.5
O2—Pb1—Br1128.41 (8)C2—N1—H1B109.5
O2i—Pb1—Br1160.31 (8)H1A—N1—H1B109.5
O1—Pb1—Br295.04 (8)C2—N1—H1C109.5
O2—Pb1—Br285.64 (8)H1A—N1—H1C109.5
O2i—Pb1—Br283.02 (8)H1B—N1—H1C109.5
Br1—Pb1—Br294.121 (16)O2—C4—O1122.1 (5)
O1—Pb1—Br2ii79.18 (9)O2—C4—C3118.2 (4)
O2—Pb1—Br2ii83.38 (8)O1—C4—C3119.7 (4)
O2i—Pb1—Br2ii91.98 (8)N1—C2—C3110.9 (4)
Br1—Pb1—Br2ii93.848 (16)N1—C2—H2A109.5
Br2—Pb1—Br2ii168.93 (2)C3—C2—H2A109.5
O1—Pb1—Br1iii152.37 (8)N1—C2—H2B109.5
O2—Pb1—Br1iii143.09 (8)C3—C2—H2B109.5
O2i—Pb1—Br1iii76.84 (8)H2A—C2—H2B108.1
Br1—Pb1—Br1iii85.652 (7)C2—C3—C4113.6 (4)
Br2—Pb1—Br1iii108.126 (15)C2—C3—H3A108.9
Br2ii—Pb1—Br1iii80.144 (15)C4—C3—H3A108.9
Pb1—Br1—Pb1iv165.91 (2)C2—C3—H3B108.9
Pb1—Br2—Pb1v168.93 (2)C4—C3—H3B108.9
C4—O1—Pb194.1 (3)H3A—C3—H3B107.7
O1—Pb1—Br1—Pb1iv99.92 (12)Br1—Pb1—O2—C415.0 (3)
O2—Pb1—Br1—Pb1iv93.36 (13)Br2—Pb1—O2—C4106.8 (3)
O2i—Pb1—Br1—Pb1iv75.1 (2)Br2ii—Pb1—O2—C474.7 (3)
Br2—Pb1—Br1—Pb1iv5.66 (8)Br1iii—Pb1—O2—C4138.5 (3)
Br2ii—Pb1—Br1—Pb1iv177.96 (8)O1—Pb1—O2—Pb1i175.8 (2)
Br1iii—Pb1—Br1—Pb1iv102.24 (8)O2i—Pb1—O2—Pb1i0.0
O1—Pb1—Br2—Pb1v122.03 (13)Br1—Pb1—O2—Pb1i175.92 (5)
O2—Pb1—Br2—Pb1v172.33 (13)Br2—Pb1—O2—Pb1i84.11 (11)
O2i—Pb1—Br2—Pb1v116.36 (13)Br2ii—Pb1—O2—Pb1i94.41 (11)
Br1—Pb1—Br2—Pb1v44.07 (10)Br1iii—Pb1—O2—Pb1i30.6 (2)
Br2ii—Pb1—Br2—Pb1v180.0Pb1—O2—C4—O112.5 (5)
Br1iii—Pb1—Br2—Pb1v42.70 (10)Pb1i—O2—C4—O1165.1 (6)
O2—Pb1—O1—C46.7 (3)Pb1—O2—C4—C3166.8 (4)
O2i—Pb1—O1—C42.1 (3)Pb1i—O2—C4—C314.1 (11)
Br1—Pb1—O1—C4179.9 (3)Pb1—O1—C4—O212.8 (5)
Br2—Pb1—O1—C487.0 (3)Pb1—O1—C4—C3166.4 (4)
Br2ii—Pb1—O1—C483.5 (3)N1—C2—C3—C465.4 (6)
Br1iii—Pb1—O1—C4125.7 (3)O2—C4—C3—C248.5 (7)
O1—Pb1—O2—C46.8 (3)O1—C4—C3—C2130.8 (5)
O2i—Pb1—O2—C4169.1 (4)
Symmetry codes: (i) x, y+1, z; (ii) x+1, y, z; (iii) x, y+1/2, z1/2; (iv) x, y+1/2, z+1/2; (v) x1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O1vi0.911.932.843 (6)177
N1—H1B···Br1vii0.912.553.422 (5)162
N1—H1C···Br2ii0.912.753.604 (5)156
N1—H1C···Br2i0.912.983.490 (4)118
Symmetry codes: (i) x, y+1, z; (ii) x+1, y, z; (vi) x+1, y+1, z+1; (vii) x+1, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula[PbBr2(C3H7NO2)]
Mr456.11
Crystal system, space groupMonoclinic, P21/c
Temperature (K)82
a, b, c (Å)6.0073 (4), 16.5286 (10), 8.3057 (5)
β (°) 100.56 (1)
V3)810.71 (9)
Z4
Radiation typeMo Kα
µ (mm1)30.60
Crystal size (mm)0.11 × 0.08 × 0.06
Data collection
DiffractometerBruker–Siemens SMART APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.066, 0.159
No. of measured, independent and
observed [I > 2σ(I)] reflections
7447, 1423, 1366
Rint0.034
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.018, 0.042, 1.20
No. of reflections1423
No. of parameters84
No. of restraints48
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.11, 0.68

Computer programs: SMART (Bruker, 2002), SAINT-Plus (Bruker, 2001), SAINT-Plus, SHELXTL (Bruker, 2000), SHELXTL.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O1i0.911.932.843 (6)177
N1—H1B···Br1ii0.912.553.422 (5)162
N1—H1C···Br2iii0.912.753.604 (5)156
N1—H1C···Br2iv0.912.983.490 (4)118
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y+1/2, z+1/2; (iii) x+1, y, z; (iv) x, y+1, z.
 

Subscribe to Acta Crystallographica Section E: Crystallographic Communications

The full text of this article is available to subscribers to the journal.

If you have already registered and are using a computer listed in your registration details, please email support@iucr.org for assistance.

Buy online

You may purchase this article in PDF and/or HTML formats. For purchasers in the European Community who do not have a VAT number, VAT will be added at the local rate. Payments to the IUCr are handled by WorldPay, who will accept payment by credit card in several currencies. To purchase the article, please complete the form below (fields marked * are required), and then click on `Continue'.
E-mail address* 
Repeat e-mail address* 
(for error checking) 

Format*   PDF (US $40)
   HTML (US $40)
   PDF+HTML (US $50)
In order for VAT to be shown for your country javascript needs to be enabled.

VAT number 
(non-UK EC countries only) 
Country* 
 

Terms and conditions of use
Contact us

Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds