Crystal structure of a second monoclinic polymorph of 3-meth­oxy­benzoic acid with Z′ = 1

A second polymorph of 3-meth­oxy­benzoic acid with Z′ = 1 is reported and compared with first polymorph with Z′ = 2.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.038
• wR factor = 0.113
• Data-to-parameter ratio = 24.3

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT355_ALERT_3_C Long   O-H (X0.82,N0.98A)  O2       - H1O2     .       1.01 Ang.
PLAT911_ALERT_3_C Missing FCF Refl Between Thmin & STh/L=    0.600         22 Report

Alert level G
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          1 Note
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         26 Note
PLAT913_ALERT_3_G Missing # of Very Strong Reflections in FCF ....          1 Note
PLAT933_ALERT_2_G Number of OMIT Records in Embedded .res File ...          1 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          7 Info

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   5 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

3-Methoxybenzoic acid

Crystal data

C8H8O3	F(000) = 320
Mr = 152.14	Dx = 1.423 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 3.8018 (4) Å	Cell parameters from 3889 reflections
b = 15.6027 (16) Å	θ = 2.6–32.4°
c = 11.9755 (12) Å	µ = 0.11 mm^−1
β = 90.889 (2)°	T = 100 K
V = 710.28 (13) Å^3	Plate, colourless
Z = 4	0.56 × 0.22 × 0.12 mm

Data collection

Bruker SMART APEXII DUO CCD diffractometer	2550 independent reflections
Radiation source: fine-focus sealed tube	2049 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
φ and ω scans	θmax = 32.6°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −5→5
Tmin = 0.881, Tmax = 0.987	k = −21→23
9395 measured reflections	l = −18→17

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.038	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.113	w = 1/[σ^2(Fo^2) + (0.0616P)^2 + 0.1229P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max = 0.001
2550 reflections	Δρmax = 0.40 e Å^−3
105 parameters	Δρmin = −0.27 e Å^−3
0 restraints

Special details

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.20200 (18)	0.96657 (4)	0.88546 (5)	0.02247 (16)
O2	−0.04494 (18)	0.88699 (4)	1.01876 (5)	0.02142 (16)
H1O2	−0.091 (5)	0.9451 (12)	1.0523 (16)	0.068 (5)*
O3	0.17686 (17)	0.58676 (4)	0.92170 (5)	0.01959 (15)
C1	0.2204 (2)	0.81461 (6)	0.86862 (7)	0.01512 (16)
C2	0.1573 (2)	0.73618 (6)	0.91952 (7)	0.01515 (16)
H2A	0.0504	0.7341	0.9906	0.018*
C3	0.2516 (2)	0.66069 (5)	0.86565 (7)	0.01517 (16)
C4	0.4082 (2)	0.66360 (6)	0.76109 (7)	0.01698 (17)
H4A	0.4738	0.6121	0.7245	0.020*
C5	0.4674 (2)	0.74261 (6)	0.71099 (7)	0.01847 (18)
H5A	0.5727	0.7447	0.6396	0.022*
C6	0.3755 (2)	0.81821 (6)	0.76329 (7)	0.01759 (17)
H6A	0.4169	0.8718	0.7283	0.021*
C7	0.1244 (2)	0.89573 (6)	0.92491 (7)	0.01636 (17)
C8	0.2877 (2)	0.50822 (6)	0.87173 (7)	0.01985 (18)
H8A	0.2229	0.4601	0.9198	0.030*
H8B	0.5434	0.5091	0.8628	0.030*
H8C	0.1726	0.5017	0.7984	0.030*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0301 (3)	0.0151 (3)	0.0223 (3)	−0.0001 (2)	0.0063 (2)	0.0011 (2)
O2	0.0285 (3)	0.0176 (3)	0.0184 (3)	0.0009 (2)	0.0077 (2)	−0.0004 (2)
O3	0.0254 (3)	0.0134 (3)	0.0202 (3)	0.0012 (2)	0.0073 (2)	0.0000 (2)
C1	0.0147 (3)	0.0151 (4)	0.0156 (3)	0.0003 (3)	0.0006 (2)	−0.0005 (3)
C2	0.0151 (3)	0.0165 (4)	0.0139 (3)	0.0002 (3)	0.0018 (2)	−0.0004 (3)
C3	0.0146 (3)	0.0150 (4)	0.0159 (3)	0.0000 (3)	0.0013 (2)	0.0001 (3)
C4	0.0161 (3)	0.0190 (4)	0.0160 (3)	0.0008 (3)	0.0025 (3)	−0.0026 (3)
C5	0.0175 (4)	0.0231 (4)	0.0149 (4)	−0.0005 (3)	0.0035 (3)	−0.0001 (3)
C6	0.0182 (4)	0.0183 (4)	0.0164 (4)	−0.0009 (3)	0.0023 (3)	0.0021 (3)
C7	0.0164 (3)	0.0170 (4)	0.0157 (3)	0.0006 (3)	0.0008 (3)	0.0001 (3)
C8	0.0217 (4)	0.0141 (4)	0.0238 (4)	0.0017 (3)	0.0033 (3)	−0.0029 (3)

Geometric parameters (Å, º)

O1—C7	1.2394 (10)	C3—C4	1.3956 (12)
O2—C7	1.3110 (10)	C4—C5	1.3909 (12)
O2—H1O2	1.01 (2)	C4—H4A	0.9500
O3—C3	1.3666 (10)	C5—C6	1.3829 (12)
O3—C8	1.4301 (10)	C5—H5A	0.9500
C1—C2	1.3896 (12)	C6—H6A	0.9500
C1—C6	1.4019 (11)	C8—H8A	0.9800
C1—C7	1.4823 (12)	C8—H8B	0.9800
C2—C3	1.3925 (12)	C8—H8C	0.9800
C2—H2A	0.9500
C7—O2—H1O2	109.8 (11)	C6—C5—H5A	119.4
C3—O3—C8	116.94 (7)	C4—C5—H5A	119.4
C2—C1—C6	120.52 (8)	C5—C6—C1	119.09 (8)
C2—C1—C7	120.47 (7)	C5—C6—H6A	120.5
C6—C1—C7	119.01 (8)	C1—C6—H6A	120.5
C1—C2—C3	119.62 (7)	O1—C7—O2	122.85 (8)
C1—C2—H2A	120.2	O1—C7—C1	121.76 (7)
C3—C2—H2A	120.2	O2—C7—C1	115.39 (7)
O3—C3—C2	115.43 (7)	O3—C8—H8A	109.5
O3—C3—C4	124.26 (7)	O3—C8—H8B	109.5
C2—C3—C4	120.31 (8)	H8A—C8—H8B	109.5
C5—C4—C3	119.34 (8)	O3—C8—H8C	109.5
C5—C4—H4A	120.3	H8A—C8—H8C	109.5
C3—C4—H4A	120.3	H8B—C8—H8C	109.5
C6—C5—C4	121.13 (8)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1O2···O1^i	1.008 (19)	1.626 (19)	2.6295 (9)	173.3 (17)
C8—H8A···O3^ii	0.98	2.56	3.4016 (11)	144

Symmetry codes: (i) −x, −y+2, −z+2; (ii) −x, −y+1, −z+2.