journal menu
research papers
The second polymorph of the compound 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT) is reported, TPT-II, which crystallizes in space group I2/a. Its higher density and more efficient space filling indicate the lower entropy of TPT-II, while its slightly lower melting point indicates its weaker intermolecular interactions. The conditions of the crystallization experiments for TPT-I and TPT-II are the dominant factors that determine the final crystalline products. The crystals of TPT-II are long needles. They exhibit bending behaviour along the crystallographic b direction when a mechanical force is imposed perpendicular to it, and regain their original shape after the external stress is removed. The elasticity of the single crystals is interpreted in terms of intermolecular interactions and an energy framework analysis.
Keywords: polymorphs; bending elasticity; intermolecular interactions; energy framework; crystal structure; phase transitions; elasticity.
Supporting information
 | Crystallographic Information File (CIF) https://doi.org/10.1107/S2052520619012514/rm5020sup1.cif |
 | Structure factor file (CIF format) https://doi.org/10.1107/S2052520619012514/rm5020Isup2.hkl |
 | Portable Document Format (PDF) file https://doi.org/10.1107/S2052520619012514/rm5020sup3.pdf |
CCDC reference: 1944221
Computing details top
Data collection: CrysAlis PRO 1.171.39.46e (Rigaku OD, 2018); cell refinement: CrysAlis PRO 1.171.39.46e (Rigaku OD, 2018); data reduction: CrysAlis PRO 1.171.39.46e (Rigaku OD, 2018); program(s) used to solve structure: ShelXT (Sheldrick, 2015); program(s) used to refine structure: SHELXL (Sheldrick, 2015); molecular graphics: Olex2 (Dolomanov et al., 2009); software used to prepare material for publication: Olex2 (Dolomanov et al., 2009).
(I) top
Crystal data top
| 0.67(C18H12N6) | F(000) = 1296 |
| Mr = 208.22 | Dx = 1.485 Mg m−3 |
| Monoclinic, I2/a | Mo Kα radiation, λ = 0.71073 Å |
| a = 21.3047 (16) Å | Cell parameters from 2299 reflections |
| b = 3.7345 (2) Å | θ = 2.2–28.1° |
| c = 35.1825 (19) Å | µ = 0.10 mm−1 |
| β = 93.364 (6)° | T = 100 K |
| V = 2794.4 (3) Å3 | Needle, colourless |
| Z = 12 | 0.84 × 0.08 × 0.03 mm |
Data collection top
| XtaLAB AFC12 (RINC): Kappa single diffractometer | 3387 independent reflections |
| Radiation source: Rotating-anode X-ray tube (dual wavelength), Rigaku (Mo) X-ray DW Source | 2267 reflections with I > 2σ(I) |
| Mirror monochromator | Rint = 0.077 |
| ω scans | θmax = 29.3°, θmin = 2.2° |
| Absorption correction: analytical CrysAlisPro 1.171.39.46e (Rigaku Oxford Diffraction, 2018) Analytical numeric absorption correction using a multifaceted crystal model based on expressions derived by R.C. Clark & J.S. Reid. (Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. | h = −28→27 |
| Tmin = 0.995, Tmax = 0.999 | k = −4→5 |
| 15782 measured reflections | l = −44→47 |
Refinement top
| Refinement on F2 | 0 restraints |
| Least-squares matrix: full | Hydrogen site location: difference Fourier map |
| R[F2 > 2σ(F2)] = 0.061 | All H-atom parameters refined |
| wR(F2) = 0.161 | w = 1/[σ2(Fo2) + (0.064P)2 + 4.3398P] where P = (Fo2 + 2Fc2)/3 |
| S = 1.04 | (Δ/σ)max < 0.001 |
| 3387 reflections | Δρmax = 0.36 e Å−3 |
| 265 parameters | Δρmin = −0.31 e Å−3 |
Special details top
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 (Å2) top
| x | y | z | Uiso*/Ueq | ||
| C1 | 0.46649 (10) | 0.4336 (5) | 0.37519 (5) | 0.0157 (4) | |
| C2 | 0.55623 (10) | 0.4524 (6) | 0.34435 (5) | 0.0161 (4) | |
| C3 | 0.55512 (10) | 0.6574 (5) | 0.40463 (5) | 0.0158 (4) | |
| C4 | 0.39873 (10) | 0.3470 (6) | 0.37539 (5) | 0.0166 (4) | |
| C5 | 0.36736 (10) | 0.1794 (6) | 0.34434 (6) | 0.0178 (5) | |
| H5 | 0.3907 (12) | 0.100 (7) | 0.3225 (7) | 0.026 (7)* | |
| C6 | 0.30406 (11) | 0.1097 (6) | 0.34547 (6) | 0.0198 (5) | |
| H6 | 0.2813 (12) | 0.002 (7) | 0.3241 (7) | 0.023 (6)* | |
| C7 | 0.30057 (11) | 0.3514 (6) | 0.40471 (6) | 0.0198 (5) | |
| H7 | 0.2755 (11) | 0.415 (7) | 0.4245 (7) | 0.023 (6)* | |
| C8 | 0.36359 (10) | 0.4354 (6) | 0.40641 (6) | 0.0180 (5) | |
| H8 | 0.3822 (11) | 0.565 (7) | 0.4282 (7) | 0.019 (6)* | |
| C9 | 0.59187 (10) | 0.3819 (5) | 0.30983 (5) | 0.0165 (4) | |
| C10 | 0.65489 (10) | 0.4706 (6) | 0.30943 (6) | 0.0176 (5) | |
| H10 | 0.6778 (12) | 0.569 (7) | 0.3314 (8) | 0.029 (7)* | |
| C11 | 0.68562 (11) | 0.4096 (6) | 0.27623 (6) | 0.0195 (5) | |
| H11 | 0.7307 (11) | 0.465 (6) | 0.2762 (6) | 0.013 (5)* | |
| C12 | 0.59733 (11) | 0.1828 (6) | 0.24561 (6) | 0.0196 (5) | |
| H12 | 0.5774 (11) | 0.058 (7) | 0.2226 (7) | 0.023 (6)* | |
| C13 | 0.56207 (10) | 0.2323 (6) | 0.27722 (6) | 0.0176 (5) | |
| H13 | 0.5182 (12) | 0.168 (6) | 0.2761 (6) | 0.017 (6)* | |
| C14 | 0.58985 (10) | 0.8110 (6) | 0.43863 (5) | 0.0166 (4) | |
| C15 | 0.56255 (11) | 0.8173 (6) | 0.47367 (6) | 0.0179 (5) | |
| H15 | 0.5189 (12) | 0.727 (7) | 0.4764 (7) | 0.019 (6)* | |
| C16 | 0.59785 (11) | 0.9522 (6) | 0.50500 (6) | 0.0194 (5) | |
| H16 | 0.5821 (12) | 0.959 (7) | 0.5310 (8) | 0.031 (7)* | |
| C17 | 0.68175 (11) | 1.0684 (6) | 0.46954 (6) | 0.0204 (5) | |
| H17 | 0.7239 (12) | 1.159 (6) | 0.4687 (6) | 0.015 (6)* | |
| C18 | 0.65064 (10) | 0.9411 (6) | 0.43652 (6) | 0.0183 (5) | |
| H18 | 0.6722 (13) | 0.937 (7) | 0.4143 (8) | 0.033 (7)* | |
| N1 | 0.49564 (9) | 0.3601 (5) | 0.34331 (5) | 0.0177 (4) | |
| N2 | 0.58829 (9) | 0.6047 (5) | 0.37388 (5) | 0.0178 (4) | |
| N3 | 0.49416 (8) | 0.5796 (5) | 0.40674 (5) | 0.0177 (4) | |
| N4 | 0.26973 (9) | 0.1931 (5) | 0.37504 (5) | 0.0213 (4) | |
| N5 | 0.65767 (9) | 0.2697 (5) | 0.24436 (5) | 0.0201 (4) | |
| N6 | 0.65636 (9) | 1.0758 (5) | 0.50378 (5) | 0.0203 (4) |
Atomic displacement parameters (Å2) top
| U11 | U22 | U33 | U12 | U13 | U23 | |
| C1 | 0.0245 (11) | 0.0154 (10) | 0.0072 (9) | −0.0005 (8) | 0.0009 (8) | 0.0023 (8) |
| C2 | 0.0244 (11) | 0.0163 (10) | 0.0076 (9) | 0.0011 (9) | 0.0008 (8) | −0.0003 (8) |
| C3 | 0.0247 (11) | 0.0164 (10) | 0.0064 (9) | 0.0016 (9) | 0.0010 (8) | 0.0013 (8) |
| C4 | 0.0238 (11) | 0.0175 (10) | 0.0086 (9) | 0.0013 (8) | 0.0009 (8) | 0.0026 (8) |
| C5 | 0.0264 (11) | 0.0198 (11) | 0.0072 (9) | 0.0007 (9) | 0.0010 (8) | 0.0006 (8) |
| C6 | 0.0258 (12) | 0.0222 (11) | 0.0110 (10) | −0.0001 (9) | −0.0017 (8) | 0.0000 (9) |
| C7 | 0.0242 (11) | 0.0235 (11) | 0.0120 (10) | 0.0007 (9) | 0.0043 (8) | −0.0014 (8) |
| C8 | 0.0256 (11) | 0.0204 (11) | 0.0078 (9) | 0.0007 (9) | 0.0009 (8) | −0.0011 (8) |
| C9 | 0.0249 (11) | 0.0174 (10) | 0.0074 (9) | 0.0017 (9) | 0.0018 (8) | 0.0005 (8) |
| C10 | 0.0237 (11) | 0.0222 (11) | 0.0068 (9) | 0.0001 (9) | 0.0006 (8) | −0.0011 (8) |
| C11 | 0.0242 (12) | 0.0236 (11) | 0.0108 (10) | 0.0023 (9) | 0.0026 (8) | 0.0004 (9) |
| C12 | 0.0288 (12) | 0.0220 (11) | 0.0079 (9) | 0.0017 (9) | −0.0001 (8) | −0.0011 (8) |
| C13 | 0.0219 (11) | 0.0205 (11) | 0.0104 (10) | 0.0009 (9) | 0.0007 (8) | 0.0004 (8) |
| C14 | 0.0226 (11) | 0.0179 (10) | 0.0090 (9) | 0.0025 (9) | −0.0019 (8) | 0.0003 (8) |
| C15 | 0.0226 (11) | 0.0201 (11) | 0.0111 (10) | 0.0009 (9) | 0.0011 (8) | −0.0003 (8) |
| C16 | 0.0271 (12) | 0.0225 (11) | 0.0086 (9) | 0.0024 (9) | 0.0004 (8) | −0.0003 (8) |
| C17 | 0.0232 (12) | 0.0247 (11) | 0.0130 (10) | −0.0015 (9) | −0.0019 (8) | 0.0012 (9) |
| C18 | 0.0259 (12) | 0.0194 (11) | 0.0097 (9) | 0.0014 (9) | 0.0023 (8) | 0.0001 (8) |
| N1 | 0.0247 (10) | 0.0200 (9) | 0.0085 (8) | 0.0002 (8) | 0.0014 (7) | −0.0002 (7) |
| N2 | 0.0242 (10) | 0.0221 (9) | 0.0072 (8) | −0.0001 (8) | 0.0008 (7) | −0.0009 (7) |
| N3 | 0.0228 (9) | 0.0216 (9) | 0.0084 (8) | −0.0011 (8) | 0.0001 (7) | 0.0002 (7) |
| N4 | 0.0238 (10) | 0.0256 (10) | 0.0145 (9) | −0.0016 (8) | 0.0017 (7) | 0.0004 (8) |
| N5 | 0.0270 (10) | 0.0235 (10) | 0.0101 (8) | 0.0019 (8) | 0.0025 (7) | −0.0011 (7) |
| N6 | 0.0283 (11) | 0.0237 (10) | 0.0085 (8) | 0.0017 (8) | −0.0013 (7) | −0.0016 (7) |
Geometric parameters (Å, º) top
| C1—C4 | 1.480 (3) | C9—C13 | 1.395 (3) |
| C1—N1 | 1.342 (3) | C10—H10 | 0.96 (3) |
| C1—N3 | 1.342 (3) | C10—C11 | 1.391 (3) |
| C2—C9 | 1.493 (3) | C11—H11 | 0.98 (2) |
| C2—N1 | 1.335 (3) | C11—N5 | 1.344 (3) |
| C2—N2 | 1.336 (3) | C12—H12 | 1.01 (3) |
| C3—C14 | 1.485 (3) | C12—C13 | 1.390 (3) |
| C3—N2 | 1.341 (3) | C12—N5 | 1.329 (3) |
| C3—N3 | 1.337 (3) | C13—H13 | 0.96 (2) |
| C4—C5 | 1.395 (3) | C14—C15 | 1.394 (3) |
| C4—C8 | 1.399 (3) | C14—C18 | 1.389 (3) |
| C5—H5 | 0.98 (3) | C15—H15 | 1.00 (3) |
| C5—C6 | 1.376 (3) | C15—C16 | 1.392 (3) |
| C6—H6 | 0.96 (3) | C16—H16 | 0.99 (3) |
| C6—N4 | 1.343 (3) | C16—N6 | 1.332 (3) |
| C7—H7 | 0.93 (2) | C17—H17 | 0.96 (3) |
| C7—C8 | 1.377 (3) | C17—C18 | 1.387 (3) |
| C7—N4 | 1.338 (3) | C17—N6 | 1.349 (3) |
| C8—H8 | 0.97 (3) | C18—H18 | 0.93 (3) |
| C9—C10 | 1.384 (3) | ||
| N1—C1—C4 | 117.30 (18) | C10—C11—H11 | 118.4 (13) |
| N3—C1—C4 | 117.79 (17) | N5—C11—C10 | 123.8 (2) |
| N3—C1—N1 | 124.9 (2) | N5—C11—H11 | 117.8 (13) |
| N1—C2—C9 | 117.99 (18) | C13—C12—H12 | 118.9 (14) |
| N1—C2—N2 | 125.51 (18) | N5—C12—H12 | 116.7 (14) |
| N2—C2—C9 | 116.50 (19) | N5—C12—C13 | 124.3 (2) |
| N2—C3—C14 | 116.45 (19) | C9—C13—H13 | 121.9 (14) |
| N3—C3—C14 | 118.61 (17) | C12—C13—C9 | 118.0 (2) |
| N3—C3—N2 | 124.93 (18) | C12—C13—H13 | 120.1 (14) |
| C5—C4—C1 | 121.12 (18) | C15—C14—C3 | 120.35 (19) |
| C5—C4—C8 | 117.6 (2) | C18—C14—C3 | 120.94 (18) |
| C8—C4—C1 | 121.26 (19) | C18—C14—C15 | 118.68 (19) |
| C4—C5—H5 | 120.3 (15) | C14—C15—H15 | 121.2 (14) |
| C6—C5—C4 | 119.2 (2) | C16—C15—C14 | 118.2 (2) |
| C6—C5—H5 | 120.4 (15) | C16—C15—H15 | 120.6 (14) |
| C5—C6—H6 | 120.5 (15) | C15—C16—H16 | 122.8 (16) |
| N4—C6—C5 | 123.9 (2) | N6—C16—C15 | 124.26 (19) |
| N4—C6—H6 | 115.5 (15) | N6—C16—H16 | 112.9 (16) |
| C8—C7—H7 | 120.6 (15) | C18—C17—H17 | 119.6 (14) |
| N4—C7—H7 | 114.7 (15) | N6—C17—H17 | 116.5 (14) |
| N4—C7—C8 | 124.6 (2) | N6—C17—C18 | 123.9 (2) |
| C4—C8—H8 | 121.4 (14) | C14—C18—H18 | 123.1 (17) |
| C7—C8—C4 | 118.52 (19) | C17—C18—C14 | 118.44 (19) |
| C7—C8—H8 | 120.0 (14) | C17—C18—H18 | 118.3 (17) |
| C10—C9—C2 | 120.41 (18) | C2—N1—C1 | 114.73 (17) |
| C10—C9—C13 | 118.86 (19) | C2—N2—C3 | 114.83 (19) |
| C13—C9—C2 | 120.7 (2) | C3—N3—C1 | 115.04 (17) |
| C9—C10—H10 | 122.0 (15) | C7—N4—C6 | 116.23 (19) |
| C9—C10—C11 | 118.30 (19) | C12—N5—C11 | 116.70 (18) |
| C11—C10—H10 | 119.7 (15) | C16—N6—C17 | 116.52 (18) |
Hydrogen-bond geometry (Å, º) top
| D—H···A | D—H | H···A | D···A | D—H···A |
| C10—H10···N4i | 0.96 (3) | 2.57 (3) | 3.497 (3) | 161 (2) |
| C11—H11···N5ii | 0.98 (2) | 2.67 (2) | 3.522 (3) | 144.7 (18) |
| C17—H17···N6iii | 0.96 (3) | 2.69 (3) | 3.521 (3) | 144.6 (18) |
| C18—H18···N4i | 0.93 (3) | 2.61 (3) | 3.466 (3) | 154 (2) |
| Symmetry codes: (i) x+1/2, −y+1, z; (ii) −x+3/2, −y+1/2, −z+1/2; (iii) −x+3/2, y, −z+1. |
