This study details the structural characterization of glycolide-h4 as a function of pressure to 6 GPa using neutron powder diffraction on the PEARL instrument at ISIS Neutron and Muon source. Glycolide-h4, rather than its deuterated isotopologue, was used in this study due to the difficulty of deuteration. The low background afforded by zirconia-toughened alumina anvils nevertheless enabled the collection of data suitable for structural analysis to be obtained to a pressure of 5 GPa. Glycolide-h4 undergoes a reconstructive phase transition at 0.15 GPa to a previously identified form (II), which is stable to 6 GPa.
Supporting information
CCDC references: 1582353; 1582354; 1582355; 1582356; 1582357
For all structures, data collection: ISIS data collection; cell refinement: TOPAS Academic; data reduction: Mantid; program(s) used to solve structure: CSD; program(s) used to refine structure: TOPAS Academic.
Crystal data top
C4H4O4 | V = 441.71 (6) Å3 |
Mr = 116.07 | Z = 4 |
Orthorhombic, Pbca | F(000) = 240 |
a = 5.1174 (4) Å | Dx = 1.745 Mg m−3 |
b = 7.3666 (4) Å | T = 298 K |
c = 11.7174 (10) Å | |
Data collection top
ZnS scintillator diffractometer | Scan method: time of flight |
Radiation source: Spallation source, spallation | |
Refinement top
Rp = 1.739 | Profile function: pseudo-Voigt |
Rwp = 1.737 | Background function: Chebyshev polynomial |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Biso*/Beq | Occ. (<1) |
O1 | 0.3213 (15) | 0.7188 (8) | 0.3381 (3) | 1.58 (7) | 0.5 |
C1 | 0.4015 (8) | 0.6178 (5) | 0.41281 (19) | 1.58 (7) | 0.5 |
O2 | 0.2734 (6) | 0.6107 (6) | 0.5126 (3) | 1.58 (7) | 0.5 |
C3 | 0.3658 (6) | 0.5015 (4) | 0.60739 (13) | 1.58 (7) | 0.5 |
H31 | 0.4151 (10) | 0.5952 (5) | 0.67657 (15) | 1.90 (9) | 0.5 |
H32 | 0.2016 (9) | 0.4172 (7) | 0.6350 (3) | 1.90 (9) | 0.5 |
C4 | 0.5986 (8) | 0.3822 (5) | 0.58716 (19) | 1.58 (7) | 0.5 |
O4 | 0.6789 (15) | 0.2812 (8) | 0.6618 (3) | 1.58 (7) | 0.5 |
O5 | 0.7266 (6) | 0.3894 (6) | 0.4873 (3) | 1.58 (7) | 0.5 |
C6 | 0.6342 (6) | 0.4984 (4) | 0.39266 (13) | 1.58 (7) | 0.5 |
H61 | 0.5848 (10) | 0.4048 (5) | 0.32347 (15) | 1.90 (9) | 0.5 |
H62 | 0.7984 (9) | 0.5828 (7) | 0.3650 (3) | 1.90 (9) | 0.5 |
Crystal data top
C4H4O4 | V = 407.28 (5) Å3 |
Mr = 116.07 | Z = 4 |
Orthorhombic, Pbca | F(000) = 240 |
a = 4.9209 (4) Å | Dx = 1.893 Mg m−3 |
b = 7.1818 (5) Å | T = 298 K |
c = 11.5243 (10) Å | |
Data collection top
ZnS scintillator diffractometer | Scan method: time of flight |
Radiation source: Spallation source, spallation | |
Refinement top
Rp = 1.525 | Profile function: pseudo-Voigt |
Rwp = 1.607 | Background function: Chebyshev polynomial |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Biso*/Beq | Occ. (<1) |
O1 | 0.305 (10) | 0.706 (9) | 0.328 (2) | −0.14 (6) | 0.5 |
C1 | 0.395 (4) | 0.613 (3) | 0.4078 (10) | −0.14 (6) | 0.5 |
O2 | 0.246 (2) | 0.593 (3) | 0.5047 (10) | −0.14 (6) | 0.5 |
C3 | 0.350 (3) | 0.500 (4) | 0.6070 (10) | −0.14 (6) | 0.5 |
H31 | 0.415 (9) | 0.609 (7) | 0.6676 (19) | −0.17 (8) | 0.5 |
H32 | 0.186 (5) | 0.414 (8) | 0.641 (4) | −0.17 (8) | 0.5 |
C4 | 0.593 (5) | 0.372 (4) | 0.5866 (15) | −0.14 (6) | 0.5 |
O4 | 0.661 (9) | 0.258 (7) | 0.660 (3) | −0.14 (6) | 0.5 |
O5 | 0.719 (9) | 0.371 (7) | 0.483 (3) | −0.14 (6) | 0.5 |
C6 | 0.649 (3) | 0.500 (3) | 0.3932 (7) | −0.14 (6) | 0.5 |
H61 | 0.623 (9) | 0.420 (8) | 0.313 (3) | −0.17 (8) | 0.5 |
H62 | 0.815 (5) | 0.602 (5) | 0.388 (6) | −0.17 (8) | 0.5 |
Crystal data top
C4H4O4 | V = 394.91 (5) Å3 |
Mr = 116.07 | Z = 4 |
Orthorhombic, Pbca | F(000) = 240 |
a = 4.8571 (4) Å | Dx = 1.952 Mg m−3 |
b = 7.1033 (5) Å | T = 298 K |
c = 11.4462 (10) Å | |
Data collection top
ZnS scintillator diffractometer | Scan method: time of flight |
Radiation source: Spallation source, spallation | |
Refinement top
Rp = 1.653 | Profile function: pseudo-Voigt |
Rwp = 1.621 | Background function: Chebyshev polynomial |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Biso*/Beq | Occ. (<1) |
O1 | 0.336 (12) | 0.744 (9) | 0.343 (5) | 0.22497 | 0.5 |
C1 | 0.394 (5) | 0.613 (4) | 0.4077 (12) | 0.22497 | 0.5 |
O2 | 0.248 (4) | 0.600 (4) | 0.5065 (12) | 0.22497 | 0.5 |
C3 | 0.351 (4) | 0.503 (5) | 0.6086 (11) | 0.22497 | 0.5 |
H31 | 0.417 (11) | 0.610 (8) | 0.671 (2) | 0.269964 | 0.5 |
H32 | 0.177 (6) | 0.426 (10) | 0.647 (5) | 0.269964 | 0.5 |
C4 | 0.598 (6) | 0.377 (5) | 0.5892 (16) | 0.22497 | 0.5 |
O4 | 0.701 (11) | 0.290 (9) | 0.670 (3) | 0.22497 | 0.5 |
O5 | 0.730 (10) | 0.378 (9) | 0.487 (3) | 0.22497 | 0.5 |
C6 | 0.656 (4) | 0.507 (4) | 0.3938 (10) | 0.22497 | 0.5 |
H61 | 0.630 (11) | 0.423 (9) | 0.314 (3) | 0.269964 | 0.5 |
H62 | 0.832 (6) | 0.601 (7) | 0.381 (7) | 0.269964 | 0.5 |
Crystal data top
C4H4O4 | V = 378.66 (5) Å3 |
Mr = 116.07 | Z = 4 |
Orthorhombic, Pbca | F(000) = 240 |
a = 4.7757 (4) Å | Dx = 2.036 Mg m−3 |
b = 6.9930 (5) Å | T = 298 K |
c = 11.3384 (10) Å | |
Data collection top
ZnS scintillator diffractometer | Scan method: time of flight |
Radiation source: Spallation source, spallation | |
Refinement top
Rp = 1.649 | Profile function: pseudo-Voigt |
Rwp = 1.660 | Background function: Chebyshev polynomial |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Biso*/Beq | Occ. (<1) |
O1 | 0.333 (13) | 0.747 (11) | 0.339 (5) | 0.20569 | 0.5 |
C1 | 0.402 (5) | 0.624 (4) | 0.4100 (14) | 0.20569 | 0.5 |
O2 | 0.245 (3) | 0.601 (4) | 0.5063 (13) | 0.20569 | 0.5 |
C3 | 0.349 (4) | 0.504 (5) | 0.6097 (13) | 0.20569 | 0.5 |
H31 | 0.415 (11) | 0.614 (8) | 0.672 (2) | 0.246828 | 0.5 |
H32 | 0.176 (5) | 0.420 (10) | 0.646 (5) | 0.246828 | 0.5 |
C4 | 0.602 (6) | 0.380 (5) | 0.5915 (17) | 0.20569 | 0.5 |
O4 | 0.705 (11) | 0.287 (10) | 0.672 (3) | 0.20569 | 0.5 |
O5 | 0.733 (11) | 0.377 (10) | 0.487 (3) | 0.20569 | 0.5 |
C6 | 0.663 (3) | 0.512 (4) | 0.3941 (10) | 0.20569 | 0.5 |
H61 | 0.630 (11) | 0.429 (10) | 0.314 (3) | 0.246828 | 0.5 |
H62 | 0.843 (6) | 0.608 (6) | 0.384 (7) | 0.246828 | 0.5 |
Crystal data top
C4H4O4 | V = 369.89 (6) Å3 |
Mr = 116.07 | Z = 4 |
Orthorhombic, Pbca | F(000) = 240 |
a = 4.7321 (4) Å | Dx = 2.084 Mg m−3 |
b = 6.9298 (5) Å | T = 298 K |
c = 11.2798 (11) Å | |
Data collection top
ZnS scintillator diffractometer | Scan method: time of flight |
Radiation source: Spallation source, spallation | |
Refinement top
Rp = 1.781 | Profile function: pseudo-Voigt |
Rwp = 1.795 | Background function: Chebyshev polynomial |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Biso*/Beq | Occ. (<1) |
O1 | 0.33 (2) | 0.751 (16) | 0.340 (8) | 0.29933 | 0.5 |
C1 | 0.398 (8) | 0.622 (6) | 0.409 (2) | 0.29933 | 0.5 |
O2 | 0.244 (5) | 0.602 (6) | 0.507 (2) | 0.29933 | 0.5 |
C3 | 0.343 (6) | 0.499 (8) | 0.610 (2) | 0.29933 | 0.5 |
H31 | 0.399 (18) | 0.606 (14) | 0.677 (3) | 0.359196 | 0.5 |
H32 | 0.167 (9) | 0.411 (16) | 0.642 (8) | 0.359196 | 0.5 |
C4 | 0.603 (10) | 0.379 (8) | 0.592 (3) | 0.29933 | 0.5 |
O4 | 0.706 (17) | 0.285 (16) | 0.673 (4) | 0.29933 | 0.5 |
O5 | 0.740 (17) | 0.383 (16) | 0.488 (5) | 0.29933 | 0.5 |
C6 | 0.662 (6) | 0.509 (6) | 0.3927 (16) | 0.29933 | 0.5 |
H61 | 0.625 (16) | 0.419 (16) | 0.315 (6) | 0.359196 | 0.5 |
H62 | 0.842 (10) | 0.605 (10) | 0.377 (11) | 0.359196 | 0.5 |