Structural Features of the Carbon-Sulfur Chemical Bond: a Semi-Experimental Perspective Supporting Information

Structural features of the carbon-sulfur chemical bond: a semi-experimental perspective Supporting Information

Emanuele Penocchio, Marco Mendolicchio, Nicola Tasinato, and Vincenzo

Barone∗

Scuola Normale Superiore, Pisa, Italy

∗To whom correspondence should be addressed

1 In Table 1 we focus on molecules reported in Table 2 of the main article and compare reference SE equilibrium parameters with ab-initio predictions obtained with B3LYP/SNSD, B2PLYP/VTZ, M06-2X, and BHandH model chemistries.

β In Table 2, experimental rotational constants, ∆Bvib calculated at B3LYP/SNSD and B2PLYP/VTZ β levels of theory, and ∆Bel calculated at B3LYP/AVTZ level are reported for all the species discussed in the main text.

Table 1: Comparison between reference SE equilibrium parameters and ab-initio ones obtained using functionals with a diﬀerent amount of Hartree-Fock exchange (see main text). Distances in A,˚ angles in degrees. Atom numbering as in Figure 2 of the main work.

SEa re re B3LYP/SNSD B2PLYP/VTZ M06-2X/VTZ BHandH/VTZ SE – Sulfur chains – isothiocyanic acid r(S-C) 1.5832 1.5744 1.5713 1.5588 1.5678(7) r(C-N) 1.2091 1.2047 1.1922 1.179 1.2047(9) r(N-H) 1.0102 1.0035 1.0035 0.9974 1.0070(9) a(S-C-N) 173.77 173.95 174.81 175.42 172.23(18) a(H-N-C) 129.67 131.50 134.72 137.28 129.75(5) thioformaldehyde r(S-C) 1.6227 1.6135 1.60089 1.58782 1.6093(1) r(C-H) 1.0918 1.0859 1.08702 1.0849 1.0854(2) a(H-C-S) 121.95 122.01 122.025 121.964 121.73(2) thioketene r(S-C) 1.5724 1.5623 1.5546 1.5426 1.5556(4) r(C-C) 1.3107 1.3082 1.3021 1.2899 1.3107(5) r(C-H) 1.0863 1.0801 1.0811 1.0793 1.0806(1) a(C-C-H) 120.66 120.46 120.31 129.34 120.15(1) propadienethione r(S1-C2) 1.5876 1.5776 1.5673 1.5546 1.5715(15) r(C2-C3) 1.2722 1.2691 1.2679 1.2571 1.2702(18) r(C3-C4) 1.3223 1.3191 1.3119 1.3003 1.3228(9) r(C4-H) 1.0905 1.0848 1.0851 1.0832 1.0842(3) a(H-C4-C3) 121.80 121.68 121.48 121.49 121.20(2)

2 β β Table 2: Experimental rotational constants, ∆Bvib, and ∆Bel are reported for all the species discussed in the main text. All data are in MHz, see main text for atom numbering.

β EXP β β (B0 ) −∆Bvib ∆Bel B3LYP/SNSD B2PLYP/VTZ B3LYP/AVTZ thiirane parent A 21973.6349a 200.215 211.715 −0.196 B 10824.8925a 65.624 68.231 −0.153 C 8026.24744a 65.267 68.182 0.212 33S A 21973.4850b 200.338 211.838 −0.196 B 10683.8236b 64.437 67.002 −0.148 C 7948.33140b 64.331 67.208 0.208 34S A 21973.3890b 200.467 211.955 −0.196 B 10551.1131b 63.331 65.852 −0.143 C 7874.59486b 63.451 66.291 0.205 13C A 21482.4120b 192.968 204.216 −0.187 B 10653.3545b 63.839 66.401 −0.150 C 7866.25519b 63.373 66.234 0.202 4D A 15471.0c 125.390 130.939 −0.096 B 9197.6c 53.388 54.908 −0.116 C 6819.0c 50.661 52.345 0.150 thiazole parent A 8529.403d 65.070 66.728 −0.509 B 5505.746d 31.412 32.566 −0.261 C 3344.291d 23.458 24.190 0.074 34S A 8529.220d 64.950 66.612 −0.509 B 5353.320d 30.318 31.417 −0.247 C 3287.440d 22.898 23.610 0.071 15N A 8471.550d 64.081 65.736 −0.498 B 5401.340d 30.682 31.870 −0.253 C 3296.756d 22.959 23.701 0.072 13 d C2 A 8335.696 63.323 64.956 −0.485 B 5504.919d 31.037 32.201 −0.262 C 3313.801d 23.103 23.834 0.072 13 d C4 A 8460.999 64.179 65.865 −0.505 B 5412.722d 30.737 31.817 −0.251 C 3299.390d 23.007 23.714 0.072 13 d C5 A 8317.847 62.972 64.590 −0.484 B 5505.989d 31.185 32.327 −0.261 C 3311.352d 23.108 23.828 0.072 d D2 A 7867.590 57.225 58.656 −0.433 B 5505.486d 31.441 32.560 −0.261 C 3237.439d 22.304 22.982 0.069 d D4 A 8325.228 63.225 64.838 −0.499 B 5229.035d 29.128 30.122 −0.230 C 3210.280d 22.063 22.727 0.068 d D5 A 7855.939 56.097 57.527 −0.429 B 5498.517d 31.716 32.895 −0.263 C 3233.047d 22.211 22.910 0.069

References: a) 1; b) 2; c) 3; d) 4;

3 — Table 2 continued —

β EXP β β (B0 ) −∆Bvib ∆Bel B3LYP/SNSD B2PLYP/VTZ B3LYP/AVTZ 1,2,3-thiadiazole parent A 8711.38a 65.265 67.814 −0.840 B 5847.09a 43.587 46.446 −0.319 C 3496.59a 28.651 30.087 0.072 34S A 8711.41a 65.140 67.628 −0.841 B 5686.12a 42.073 44.872 −0.301 C 3438.37a 28.016 29.431 0.070 15 a N2 A 8502.61 63.456 65.949 −0.797 B 5846.91a 43.211 45.961 −0.319 C 3462.38a 28.199 29.580 0.071 15 a N3 A 8650.57 63.832 66.238 −0.821 B 5740.43a 42.986 45.770 −0.310 C 3448.54a 28.150 29.538 0.070 13 a C4 A 8641.88 65.077 67.632 −0.836 B 5742.95a 42.139 44.936 −0.304 C 3448.07a 28.040 29.460 0.070 13 a C5 A 8486.04 62.670 65.041 −0.799 B 5847.30a 43.416 46.235 −0.319 C 3459.77a 28.139 29.522 0.070 a D4 A 8518.49 65.578 68.230 −0.826 B 5530.15a 39.050 41.553 −0.276 C 3351.31a 26.793 28.134 0.066 a D5 A 7998.72 55.213 57.234 −0.704 B 5839.27a 44.759 47.498 −0.321 C 3373.24a 27.162 28.422 0.067 34 a S, D5 A 7997.22 55.168 57.183 −0.705 B 5680.08a 43.149 45.841 −0.303 C 3319.24a 26.586 27.841 0.065 15 a N2,D5 A 7815.75 53.726 55.746 −0.668 B 5838.42a 44.426 47.025 −0.322 C 3339.97a 26.728 27.935 0.066 15 a N3,D5 A 7949.74 53.942 55.844 −0.687 B 5728.83a 44.165 46.728 −0.313 C 3327.53a 26.706 27.888 0.065 13 a C4,D5 A 7939.11 55.271 57.341 −0.703 B 5737.70a 43.209 45.904 −0.306 C 3328.66a 26.605 27.868 0.065 13 a C5,D5 A 7816.59 53.038 55.006 −0.673 B 5839.34a 44.644 47.317 −0.322 C 3340.43a 26.678 27.896 0.065 2D A 7831.12a 56.160 58.338 −0.698 B 5528.41a 39.932 42.295 −0.277 C 3238.85a 25.479 26.665 0.061

References: a) 5.

4 — Table 2 continued —

β EXP β β (B0 ) −∆Bvib ∆Bel B3LYP/SNSD B2PLYP/VTZ B3LYP/AVTZ 1,3,4-thiadiazole parent A 8907.376a 72.606 74.365 −0.599 B 5569.321a 30.842 32.573 −0.336 C 3424.779a 24.590 25.555 0.061 34S A 8907.484a 72.442 74.265 −0.599 B 5408.526a 29.745 31.414 −0.317 C 3363.296a 23.962 24.916 0.058 15N A 8838.554a 71.489 73.271 −0.590 B 5469.994a 30.167 31.892 −0.323 C 3376.938a 24.078 25.044 0.059 13C A 8696.617a 70.552 72.217 −0.571 B 5569.263a 30.531 32.225 −0.335 C 3393.119a 24.248 25.179 0.060 2D A 7565.918a 55.432 56.874 −0.431 B 5567.338a 31.016 32.603 −0.335 C 3205.561a 22.161 22.991 0.053 34S, 2D A 7566.044a 55.306 56.759 −0.431 B 5407.324a 29.911 31.424 −0.318 C 3151.862a 21.641 22.451 0.051 15N, 2D A 7517.216a 54.713 56.151 −0.426 B 5467.128a 30.307 31.898 −0.323 C 3163.478a 21.724 22.555 0.052 13C, 2D A 7413.475a 53.955 55.397 −0.414 B 5567.237a 30.730 32.273 −0.335 C 3177.816a 21.835 22.647 0.052 D A 8190.071a 63.117 64.734 −0.506 B 5568.156a 30.962 32.572 −0.336 C 3312.800a 23.347 24.229 0.057 34S, D A 8189.876a 62.992 64.610 −0.506 B 5407.830a 29.860 31.407 −0.317 C 3255.322a 22.779 23.641 0.054 15N-D A 8134.555a 62.364 63.965 −0.499 B 5469.463a 30.244 31.825 −0.323 C 3268.673a 22.887 23.756 0.056 15N, D A 8130.079a 62.123 63.748 −0.499 B 5467.331a 30.293 31.883 −0.323 C 3267.174a 22.867 23.743 0.056 13C-D A 8019.104a 61.382 62.935 −0.485 B 5568.179a 30.648 32.244 −0.335 C 3284.460a 23.004 23.866 0.056 13C, D A 8004.030a 61.433 62.992 −0.483 B 5567.949a 30.642 32.245 −0.335 C 3281.849a 23.013 23.879 0.056

References: a) 6.

5 — Table 2 continued —

β EXP β β (B0 ) −∆Bvib ∆Bel B3LYP/SNSD B2PLYP/VTZ B3LYP/AVTZ 1,2,4-thiadiazole parent A 8811.08a 64.682 67.392 0.706 B 5938.20a 35.023 36.647 0.321 C 3545.34a 25.297 26.372 0.064 34S A 8809.75a 64.462 67.263 0.707 B 5774.93a 33.833 35.375 0.303 C 3486.27a 24.705 25.762 0.061 15 a N3 A 8591.19 62.511 65.072 0.669 B 5937.86a 34.781 36.395 0.321 C 3509.06a 24.891 25.937 0.062 15 a N4 A 8759.14 63.889 66.670 0.692 B 5813.92a 34.112 35.731 0.310 C 3492.42a 24.752 25.831 0.062 13 a C3 A 8731.40 63.747 66.402 0.700 B 5848.03a 34.298 35.816 0.308 C 3500.25a 24.825 25.851 0.062 13 a C5 A 8598.97 62.769 65.424 0.671 B 5936.25a 34.659 36.265 0.321 C 3509.80a 24.889 25.948 0.062 a D5 A 8091.37 56.594 58.924 0.595 B 5937.91a 35.173 36.734 0.321 C 3422.73a 24.004 24.992 0.059 34 a S, D5 A 8090.91 56.421 58.752 0.596 B 5774.57a 33.977 35.453 0.303 C 3367.73a 23.469 24.426 0.057 15 a N2,D5 A 7897.87 54.752 57.035 0.566 B 5937.52a 34.938 36.483 0.322 C 3387.47a 23.608 24.582 0.058 15 a N3,D5 A 8052.52 56.069 58.379 0.584 B 5813.19a 34.238 35.805 0.311 C 3374.11a 23.519 24.503 0.057 13 a C3,D5 A 8019.29 55.725 58.025 0.591 B 5847.74a 34.477 35.923 0.308 C 3379.82a 23.562 24.506 0.058 13 a C5,D5 A 7920.20 55.013 57.286 0.569 B 5935.86a 34.810 36.362 0.322 C 3391.03a 23.611 24.586 0.058 1,2,5-thiadiazole parent A 8538.436b 61.913 65.788 −0.834 B 6333.038b 39.475 40.516 −0.321 C 3633.926b 26.687 27.780 0.071 34S A 8538.670b 61.655 65.513 −0.834 B 6166.960b 38.181 39.190 −0.303 C 3578.661b 26.106 27.171 0.069 15N A 8324.235b 59.821 63.587 −0.793 B 6333.303b 39.213 40.238 −0.321 C 3594.629b 26.231 27.309 0.069 13C A 8472.029b 61.185 64.926 −0.821 B 6215.713b 38.546 39.548 −0.310 C 3583.153b 26.177 27.226 0.069 2D A 8041.747b 56.591 60.218 −0.741 B 5717.785b 34.405 35.151 −0.263 C 3339.958b 23.554 24.476 0.060 34S, 2D A 8041.972b 56.372 59.999 −0.741 B 5569.697b 33.289 33.992 −0.249 C 3288.903b 23.042 23.935 0.058 15N, 2D A 7851.445b 54.835 58.293 −0.706 B 5717.895b 34.147 34.949 −0.263 C 3306.690b 23.176 24.098 0.058 13C, 2D A 7981.850b 55.814 59.359 −0.730 B 5629.614b 33.721 34.428 −0.255 C 3299.474b 23.137 24.025 0.058

References: a) 7; b) 8.

6 — Table 2 continued —

β EXP β β (B0 ) −∆Bvib ∆Bel B3LYP/SNSD B2PLYP/VTZ B3LYP/AVTZ isothiocyanic acid parent B 5883.46269a 18.859 19.119 −0.054 C 5845.61125a 21.991 22.270 −0.044 34S B 5744.83270a 18.329 18.583 −0.050 C 5708.73610a 21.319 21.592 −0.042 D B 5500.43911a 17.201 17.350 −0.047 C 5445.22521a 20.788 20.920 −0.039 13C B 5864.55243a 18.595 18.855 −0.053 C 5826.88808a 21.703 21.980 −0.044 15N B 5688.69511a 17.947 18.218 −0.051 C 5652.98346a 20.883 21.173 −0.042 thioformaldehyde parent B 17698.87b 67.713 71.660 −1.353 C 16652.98b 101.653 105.616 −0.211 34S B 17388.31b 66.294 70.168 −1.301 C 16377.80b 99.169 103.058 −0.199 13C B 16998.70b 63.236 67.039 −1.253 C 16031.65b 94.880 98.695 −0.200 2D B 14904.27b 53.1090 55.333 −0.970 C 13496.33b 81.9900 84.267 −0.149 thioketene parent B 5659.4560c 11.016 12.021 −0.081 C 5544.5000c 16.119 17.127 −0.063 34S B 5531.5592c 10.733 11.712 −0.077 C 5421.6836c 15.619 16.601 −0.060 32S-13C B 5642.6160c 10.830 11.814 −0.081 C 5528.3412c 15.905 16.893 −0.063 13 c C-H2 B 5456.6996 10.513 11.485 −0.076 C 5349.7653c 15.261 16.234 −0.059 D B 5323.0717c 10.261 11.109 −0.073 C 5176.9949c 15.473 16.327 −0.055 propadienethione parent B 2539.276d −1.362 0.606 −0.026 C 2515.681d 0.437 2.266 −0.008 34S B 2476.927d −1.326 0.586 −0.024 C 2454.456d 0.388 2.167 −0.007 13 d C3 B 2520.081 −1.206 0.698 −0.025 C 2496.829d 0.575 2.340 −0.008 13 d C4 B 2459.383 −1.398 0.507 −0.024 C 2437.248d 0.289 2.063 −0.007 D B 2421.049d −8.550 0.875 −0.023 C 2390.164d 0.956 2.572 −0.007 2D B 2317.593d −1.237 0.513 −0.022 C 2279.498d 0.808 2.389 −0.007

References: a) 9; b) 10; c) 11; d) 12.

7 — Table 2 continued —

β EXP β β (B0 ) −∆Bvib ∆Bel B3LYP/SNSD B2PLYP/VTZ B3LYP/AVTZ isocyanic acid parent A 918504.4a −50088.733 −55318.108 193.871 B 11071.0083a 35.583 36.113 −0.227 C 10910.5755a 48.574 49.100 −0.184 18O A 918416.5a −50056.141 −55290.094 193.819 B 10470.8956a 33.448 33.944 −0.199 C 10327.2423a 45.112 45.601 −0.161 15N A 908968.2a −49399.506 −54581.535 192.438 B 10737.8304a 34.081 34.650 −0.216 C 10585.4653a 46.353 46.911 −0.175 13C A 916293.8a −50043.307 −55301.167 192.509 B 11071.4798a 35.157 35.685 −0.227 C 10910.7307a 48.124 48.639 −0.184 D A 512472.3a −22191.520 −24370.944 539.180 B 10313.7131a 30.883 30.820 −0.197 C 10079.6761a 45.459 45.485 −0.161 formaldehydeb parent A 281970.558 3173.034 3138.095 −463.336 B 38833.9872 137.820 152.681 −4.925 C 34004.2435 287.228 296.347 −1.960 17O-13C A 281987.319 3156.650 3120.814 −463.336 B 36776.7902 123.956 137.934 −4.417 C 32412.9202 261.399 270.137 −1.779 18O-13C A 281984.998 3160.925 3124.941 −463.336 B 35859.2557 119.801 133.377 −4.174 C 31697.8683 251.723 260.282 −1.681 13C, 2D A 141668.408 1180.418 1171.289 −116.015 B 31733.2046 115.164 124.296 −3.376 C 25822.3934 221.520 226.180 −1.191 13C A 281993.040 3151.901 3116.221 −463.336 B 37809.1070 128.686 143.123 −4.698 C 33215.9414 272.422 281.361 −1.892 17O A 281965.030 3177.715 3142.624 −463.336 B 37812.2875 133.004 147.410 −4.638 C 33214.5233 276.139 285.062 −1.845 18O, 2D A 141648.300 1198.750 1189.897 −116.015 B 30595.8620 113.520 122.273 −3.082 C 25063.1220 213.966 218.510 −1.083 18O A 281961.216 3181.927 3146.698 −463.336 B 36902.2755 128.771 142.777 −4.392 C 32513.4059 266.398 275.146 −1.747 2D A 141653.549 1185.945 1185.843 −116.002 B 32283.5640 120.738 130.369 −3.474 C 26185.3152 228.873 234.121 −1.213 D A 198118.326 1772.827 1752.556 −226.645 B 34910.5373 130.827 142.417 −4.052 C 29561.4624 255.092 261.673 −1.515 ketene parent A 282101.195c 1478.529 1393.845 −63.707 B 10293.3213c 22.324 24.326 −0.209 C 9915.90536c 36.950 38.916 −0.146 18O A 287349.872c 1479.391 1394.934 −63.707 B 9761.23674c 21.039 22.912 −0.184 C 9421.12369c 34.306 36.149 −0.129 16O-13C A 282334.044c 1489.402 1405.669 −63.707 B 10293.6208c 21.958 23.955 −0.209 C 9916.20455c 36.588 38.554 −0.146 13 c C-H2 A 282111.898 1496.336 1409.792 −63.707 B 9960.96597c 21.664 23.596 −0.198 C 9607.12752c 35.373 37.269 −0.139 D A 194305.085c 489.5430 4493.610 −30.023 B 9647.06647c 19.486 21.105 −0.190 C 9174.64573c 34.191 35.784 −0.128 2D A 141537.116c 426.5450 3949.380 −15.955 B 9120.82968c 15.961 17.397 −0.168 C 8552.70079c 30.905 32.265 −0.113

References: a) 13; b)all data from refs 14,15; c) 16. 8 — Table 2 continued —

β EXP β β (B0 ) −∆Bvib ∆Bel B3LYP/SNSD B2PLYP/VTZ B3LYP/AVTZ propadienone parent A 143807.0a −13911.744 −13832.384 −222.240 B 4387.047a 36.546 40.023 −0.088 C 4258.119a 31.602 34.252 −0.040 18O A 160249.0a −13915.480 −13834.317 −220.843 B 4167.825a 34.324 37.586 −0.078 C 4050.928a 29.847 32.359 −0.035 13 a C1 A 155643.0 −13914.103 −13837.176 −222.238 B 4373.458a 36.438 39.916 −0.087 C 4245.312a 31.516 34.169 −0.040 13 a C3 A 144753.0 −13983.634 −13895.295 −219.378 B 4255.807a 35.683 39.125 −0.083 C 4133.492a 30.872 33.511 −0.038 a Dc A 107397.0 −6747.7650 −6697.4220 −110.244 B 4227.953a 34.431 37.142 −0.082 C 4059.208a 29.953 32.034 −0.037 a Dt A 139122.0 −7683.6970 −8010.5720 −192.027 B 4124.758a 26.153 28.902 −0.079 C 4001.074a 24.391 26.542 −0.036

References: a) 17.

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