Heptane-1,7-diaminium dinitrate.

In the title molecular salt, C(7)H(20)N(2) (2+)·2NO(3) (-), the crystal structure exhibits an unusual back-to-back paired double-stacked packing arrangement culminating in an overall double zigzag pattern of the dications. The nitrate anions form a ring around one pair of double-stacked dications. An intricate three-dimensional N-H⋯O and N-H⋯(O,O) hydrogen-bonding network exists in the crystal structure.

Related literature

For related structural studies of n-alkyl-diammonium nitrate salts, see: van Blerk & Kruger (2009 ▶). For the Cambridge Structural Database, see: Allen (2002 ▶).

Experimental

Crystal data

C7H20N2 2+·2NO3 −

M = 256.27

Monoclinic,

a = 5.3236 (1) Å

b = 16.8340 (4) Å

c = 14.9845 (3) Å

β = 96.500 (1)°

V = 1334.24 (5) Å3

Z = 4

Mo Kα radiation

μ = 0.11 mm−1

T = 295 K

0.44 × 0.35 × 0.32 mm

Data collection

Bruker SMART CCD diffractometer

Absorption correction: multi-scan (AX-SCALE; Bruker, 2008 ▶) T min = 0.953, T max = 0.966

16750 measured reflections

2343 independent reflections

1828 reflections with I > 2σ(I)

R int = 0.032

Refinement

R[F 2 > 2σ(F 2)] = 0.042

wR(F 2) = 0.124

S = 1.06

2343 reflections

157 parameters

H-atom parameters constrained

Δρmax = 0.29 e Å−3

Δρmin = −0.18 e Å−3

Data collection: SMART-NT (Bruker, 1999 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▶) and Mercury (Macrae et al., 2008 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶) and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536811042917/ez2262sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811042917/ez2262Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536811042917/ez2262Isup3.mol

Supplementary material file. DOI: 10.1107/S1600536811042917/ez2262Isup4.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C7H20N22+·2NO3−	F(000) = 552
Mr = 256.27	Dx = 1.276 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 8072 reflections
a = 5.3236 (1) Å	θ = 2.4–24.5°
b = 16.8340 (4) Å	µ = 0.11 mm−1
c = 14.9845 (3) Å	T = 295 K
β = 96.500 (1)°	Block, colourless
V = 1334.24 (5) Å3	0.44 × 0.35 × 0.32 mm
Z = 4

Bruker SMART CCD diffractometer	2343 independent reflections
Radiation source: fine-focus sealed tube	1828 reflections with I > 2σ(I)
graphite	Rint = 0.032
φ and ω scans	θmax = 25.0°, θmin = 1.8°
Absorption correction: multi-scan (AX-SCALE; Bruker, 2008)	h = −6→6
Tmin = 0.953, Tmax = 0.966	k = −19→19
16750 measured reflections	l = −17→17

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)] = 0.042	H-atom parameters constrained
wR(F2) = 0.124	w = 1/[σ2(Fo2) + (0.0558P)2 + 0.3767P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max < 0.001
2343 reflections	Δρmax = 0.29 e Å−3
157 parameters	Δρmin = −0.18 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.027 (3)

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.

	x	y	z	Uiso*/Ueq
C1	0.2521 (4)	0.71038 (12)	0.43729 (16)	0.0700 (6)
H1A	0.1900	0.6662	0.3994	0.084*
H1B	0.1282	0.7213	0.4784	0.084*
C2	0.4951 (4)	0.68708 (14)	0.48992 (15)	0.0703 (6)
H2A	0.5671	0.7331	0.5223	0.084*
H2B	0.6127	0.6703	0.4487	0.084*
C3	0.4660 (4)	0.62061 (13)	0.55650 (14)	0.0683 (6)
H3A	0.3515	0.6380	0.5986	0.082*
H3B	0.3899	0.5751	0.5243	0.082*
C4	0.7127 (4)	0.59522 (14)	0.60854 (15)	0.0724 (6)
H4A	0.8182	0.5710	0.5673	0.087*
H4B	0.8000	0.6420	0.6339	0.087*
C5	0.6812 (4)	0.53735 (13)	0.68327 (14)	0.0670 (5)
H5A	0.5906	0.4911	0.6580	0.080*
H5B	0.5781	0.5620	0.7249	0.080*
C6	0.9287 (4)	0.50997 (13)	0.73523 (13)	0.0617 (5)
H6A	1.0223	0.4783	0.6962	0.074*
H6B	1.0306	0.5560	0.7543	0.074*
C7	0.8826 (3)	0.46172 (11)	0.81595 (13)	0.0571 (5)
H7A	0.7854	0.4931	0.8541	0.068*
H7B	0.7831	0.4153	0.7965	0.068*
N1	0.2774 (3)	0.78115 (9)	0.38028 (11)	0.0612 (4)
H1C	0.3176	0.8232	0.4150	0.092*
H1D	0.1315	0.7901	0.3466	0.092*
H1E	0.3983	0.7727	0.3449	0.092*
N2	1.1202 (3)	0.43572 (9)	0.86872 (10)	0.0563 (4)
H2C	1.1956	0.3994	0.8378	0.084*
H2D	1.0855	0.4148	0.9205	0.084*
H2E	1.2224	0.4773	0.8796	0.084*
N3	0.2584 (3)	0.77064 (11)	0.75577 (11)	0.0643 (5)
N4	0.3365 (3)	0.60428 (9)	0.97456 (10)	0.0524 (4)
O1	0.2441 (3)	0.70920 (9)	0.80187 (11)	0.0828 (5)
O2	0.0960 (4)	0.82199 (13)	0.75256 (13)	0.1094 (7)
O3	0.4470 (3)	0.78063 (11)	0.71661 (13)	0.0983 (6)
O4	0.1024 (2)	0.59148 (8)	0.96594 (8)	0.0579 (4)
O5	0.4312 (3)	0.65102 (10)	1.03157 (11)	0.0859 (5)
O6	0.4699 (3)	0.56836 (8)	0.92489 (11)	0.0731 (4)

	U11	U22	U33	U12	U13	U23
C1	0.0538 (11)	0.0625 (12)	0.0923 (15)	−0.0014 (9)	0.0016 (10)	0.0079 (11)
C2	0.0556 (11)	0.0777 (14)	0.0755 (13)	−0.0033 (10)	−0.0012 (10)	0.0081 (11)
C3	0.0584 (12)	0.0721 (13)	0.0727 (13)	−0.0007 (10)	−0.0003 (10)	0.0041 (11)
C4	0.0593 (12)	0.0834 (15)	0.0729 (13)	−0.0023 (11)	0.0004 (10)	0.0120 (11)
C5	0.0561 (11)	0.0755 (13)	0.0683 (12)	−0.0021 (10)	0.0020 (9)	0.0050 (10)
C6	0.0528 (11)	0.0696 (12)	0.0624 (11)	−0.0009 (9)	0.0045 (9)	0.0033 (10)
C7	0.0504 (10)	0.0580 (11)	0.0631 (11)	0.0000 (8)	0.0078 (8)	−0.0033 (9)
N1	0.0513 (9)	0.0562 (9)	0.0743 (11)	0.0003 (7)	0.0001 (8)	−0.0044 (8)
N2	0.0582 (9)	0.0552 (9)	0.0548 (9)	0.0062 (7)	0.0033 (7)	−0.0041 (7)
N3	0.0607 (10)	0.0703 (11)	0.0601 (10)	−0.0032 (9)	−0.0014 (8)	0.0114 (8)
N4	0.0455 (9)	0.0497 (9)	0.0609 (9)	0.0030 (7)	0.0016 (7)	0.0092 (7)
O1	0.0805 (11)	0.0728 (10)	0.0962 (11)	−0.0081 (8)	0.0145 (8)	0.0310 (9)
O2	0.0942 (13)	0.1239 (15)	0.1122 (14)	0.0452 (12)	0.0216 (11)	0.0440 (12)
O3	0.0797 (11)	0.1003 (13)	0.1192 (14)	−0.0011 (9)	0.0293 (10)	0.0406 (11)
O4	0.0425 (7)	0.0639 (8)	0.0674 (8)	0.0010 (6)	0.0061 (6)	0.0046 (6)
O5	0.0768 (11)	0.0803 (11)	0.0948 (11)	−0.0076 (8)	−0.0155 (9)	−0.0181 (9)
O6	0.0574 (8)	0.0696 (9)	0.0967 (11)	0.0094 (7)	0.0286 (8)	0.0016 (8)

C1—N1	1.481 (3)	C6—H6A	0.9700
C1—C2	1.489 (3)	C6—H6B	0.9700
C1—H1A	0.9700	C7—N2	1.480 (2)
C1—H1B	0.9700	C7—H7A	0.9700
C2—C3	1.519 (3)	C7—H7B	0.9700
C2—H2A	0.9700	N1—H1C	0.8900
C2—H2B	0.9700	N1—H1D	0.8900
C3—C4	1.511 (3)	N1—H1E	0.8900
C3—H3A	0.9700	N2—H2C	0.8900
C3—H3B	0.9700	N2—H2D	0.8900
C4—C5	1.508 (3)	N2—H2E	0.8900
C4—H4A	0.9700	N3—O2	1.220 (2)
C4—H4B	0.9700	N3—O3	1.230 (2)
C5—C6	1.524 (3)	N3—O1	1.251 (2)
C5—H5A	0.9700	N4—O5	1.227 (2)
C5—H5B	0.9700	N4—O6	1.2424 (19)
C6—C7	1.500 (3)	N4—O4	1.2570 (18)
N1—C1—C2	112.78 (17)	C7—C6—C5	111.39 (16)
N1—C1—H1A	109.0	C7—C6—H6A	109.4
C2—C1—H1A	109.0	C5—C6—H6A	109.4
N1—C1—H1B	109.0	C7—C6—H6B	109.4
C2—C1—H1B	109.0	C5—C6—H6B	109.4
H1A—C1—H1B	107.8	H6A—C6—H6B	108.0
C1—C2—C3	113.25 (18)	N2—C7—C6	112.51 (15)
C1—C2—H2A	108.9	N2—C7—H7A	109.1
C3—C2—H2A	108.9	C6—C7—H7A	109.1
C1—C2—H2B	108.9	N2—C7—H7B	109.1
C3—C2—H2B	108.9	C6—C7—H7B	109.1
H2A—C2—H2B	107.7	H7A—C7—H7B	107.8
C4—C3—C2	113.58 (17)	C1—N1—H1C	109.5
C4—C3—H3A	108.9	C1—N1—H1D	109.5
C2—C3—H3A	108.9	H1C—N1—H1D	109.5
C4—C3—H3B	108.9	C1—N1—H1E	109.5
C2—C3—H3B	108.9	H1C—N1—H1E	109.5
H3A—C3—H3B	107.7	H1D—N1—H1E	109.5
C5—C4—C3	113.76 (17)	C7—N2—H2C	109.5
C5—C4—H4A	108.8	C7—N2—H2D	109.5
C3—C4—H4A	108.8	H2C—N2—H2D	109.5
C5—C4—H4B	108.8	C7—N2—H2E	109.5
C3—C4—H4B	108.8	H2C—N2—H2E	109.5
H4A—C4—H4B	107.7	H2D—N2—H2E	109.5
C4—C5—C6	114.37 (17)	O2—N3—O3	119.83 (18)
C4—C5—H5A	108.7	O2—N3—O1	121.37 (19)
C6—C5—H5A	108.7	O3—N3—O1	118.72 (18)
C4—C5—H5B	108.7	O5—N4—O6	120.76 (16)
C6—C5—H5B	108.7	O5—N4—O4	120.40 (16)
H5A—C5—H5B	107.6	O6—N4—O4	118.84 (16)
N1—C1—C2—C3	173.40 (19)	C3—C4—C5—C6	178.89 (19)
C1—C2—C3—C4	178.6 (2)	C4—C5—C6—C7	172.16 (18)
C2—C3—C4—C5	172.1 (2)	C5—C6—C7—N2	−178.84 (16)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1C···O4i	0.89	2.16	2.956 (2)	149
N1—H1C···O6ii	0.89	2.62	3.129 (2)	118
N1—H1D···O1ii	0.89	2.09	2.951 (2)	161
N1—H1D···O3ii	0.89	2.40	3.035 (2)	129
N1—H1E···O1i	0.89	2.04	2.871 (2)	155
N1—H1E···O2i	0.89	2.43	3.208 (3)	147
N2—H2C···O2iii	0.89	2.26	3.142 (2)	172
N2—H2C···O3iii	0.89	2.26	2.911 (2)	130
N2—H2D···O4iv	0.89	2.07	2.901 (2)	155
N2—H2E···O4v	0.89	2.44	3.0064 (19)	122
N2—H2E···O6v	0.89	2.08	2.967 (2)	171

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1C⋯O4i	0.89	2.16	2.956 (2)	149
N1—H1C⋯O6ii	0.89	2.62	3.129 (2)	118
N1—H1D⋯O1ii	0.89	2.09	2.951 (2)	161
N1—H1D⋯O3ii	0.89	2.40	3.035 (2)	129
N1—H1E⋯O1i	0.89	2.04	2.871 (2)	155
N1—H1E⋯O2i	0.89	2.43	3.208 (3)	147
N2—H2C⋯O2iii	0.89	2.26	3.142 (2)	172
N2—H2C⋯O3iii	0.89	2.26	2.911 (2)	130
N2—H2D⋯O4iv	0.89	2.07	2.901 (2)	155
N2—H2E⋯O4v	0.89	2.44	3.0064 (19)	122
N2—H2E⋯O6v	0.89	2.08	2.967 (2)	171

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) .