Table 4.

Atom Groups and their Contributions to ΔH°(c) Calculations (in kJ/mol).

Entry	Atom Type	Neighbors	Contribution	Occurrences	Molecules
1	B	C3	−5771.41	10	10
2	B	C2O	−5234.3	2	2
3	B(-)	F4	−128.41	1	1
4	C sp3	H3B	927.34	3	1
5	C sp3	H3C	−774.53	5659	2598
6	C sp3	H3N	−1273.86	288	183
7	C sp3	H3N(+)	−1258.26	22	10
8	C sp3	H3O	−1273.9	493	333
9	C sp3	H3S	−1435.83	36	30
10	C sp3	H3P	−1106.35	3	1
11	C sp3	H3Si	−1323.2	116	49
12	C sp3	H2BC	1052.3	22	8
13	C sp3	H2C2	−653.47	9139	2066
14	C sp3	H2CN	−1150.33	632	346
15	C sp3	H2CN(+)	−1136.52	76	51
16	C sp3	H2CO	−1140.92	1209	753
17	C sp3	H2CS	−1313.58	180	118
18	C sp3	H2CP	−825.63	6	3
19	C sp3	H2CF	−626.92	15	14
20	C sp3	H2CCl	−616.8	81	70
21	C sp3	H2CBr	−620.8	23	20
22	C sp3	H2CJ	−685.85	12	9
23	C sp3	H2CSi	−1211.79	130	51
24	C sp3	H2N2	−1644.62	33	12
25	C sp3	H2N2(+)	−1666.85	6	6
26	C sp3	H2NO	−1630.65	8	6
27	C sp3	H2NS	−1776.97	2	1
28	C sp3	H2NS(+)	−1817.73	1	1
29	C sp3	H2NP(+)	−565.68	1	1
30	C sp3	H2O2	−1605.49	31	26
31	C sp3	H2OSi	−1715.41	1	1
32	C sp3	H2OCl	−1115.09	4	3
33	C sp3	H2S2	−1997.67	9	7
34	C sp3	HBC2	1197	6	2
35	C sp3	HC3	−529.09	1386	765
36	C sp3	HC2N	−1026.35	106	84
37	C sp3	HC2N(+)	−1004.99	43	40
38	C sp3	HC2O	−1010.37	545	330
39	C sp3	HC2S	−1179.91	34	25
40	C sp3	HC2Si	−1076.92	4	2
41	C sp3	HC2F	−486.29	5	5
42	C sp3	HC2Cl	−491.9	48	32
43	C sp3	HC2Br	−499.17	9	7
44	C sp3	HC2J	−574.72	4	3
45	C sp3	HCN2	−1514.29	5	4
46	C sp3	HCN2(+)	−1537.23	5	5
47	C sp3	HCNO	−1525.32	5	5
48	C sp3	HCNO(+)	−1522.69	4	2
49	C sp3	HCNS	−1683.66	4	2
50	C sp3	HCO2	−1473.47	63	54
51	C sp3	HCS2	−1791.66	1	1
52	C sp3	HCF2	−447.7	14	13
53	C sp3	HCFCl	−470.21	4	4
54	C sp3	HCCl2	−494.97	18	17
55	C sp3	HCClBr	−510.39	1	1
56	C sp3	HCBr2	−475.67	1	1
57	C sp3	HN3(+)	−2166.08	1	1
58	C sp3	HNO2	−1989.17	1	1
59	C sp3	HO3	−1920.79	6	6
60	C sp3	HOF2	−891.81	2	2
61	C sp3	BC3	1320.43	3	1
62	C sp3	C4	−403.7	392	287
63	C sp3	C3N	−886.44	46	34
64	C sp3	C3N(+)	−875.68	28	26
65	C sp3	C3O	−876.38	181	135
66	C sp3	C3S	−1050.27	23	19
67	C sp3	C3F	−451.56	11	6
68	C sp3	C3Cl	−355.26	9	9
69	C sp3	C3Br	−362.07	2	2
70	C sp3	C3J	−430.2	1	1
71	C sp3	C2N2(+)	−1417.05	9	9
72	C sp3	C2O2	−1331.4	42	38
73	C sp3	C2S2	−1708.54	4	1
74	C sp3	C2F2	−318.74	104	28
75	C sp3	C2FCl	−331.09	3	2
76	C sp3	C2Cl2	−357.37	7	7
77	C sp3	CN3(+)	−2020.09	19	11
78	C sp3	CN2F(+)	−1420.86	24	16
79	C sp3	CN2Cl(+)	−1451.19	2	2
80	C sp3	CNF2	−848.67	6	2
81	C sp3	CNF2(+)	−853.81	3	2
82	C sp3	CO3	−1771.57	8	7
83	C sp3	COF2	−802.95	3	3
84	C sp3	COCl2	−893.67	1	1
85	C sp3	CF3	−251.65	83	64
86	C sp3	CF2Cl	−306.09	10	8
87	C sp3	CF2Br	−319.62	5	4
88	C sp3	CFCl2	−317.2	7	7
89	C sp3	CFClBr	−276.51	1	1
90	C sp3	CCl3	−371.89	25	24
91	C sp3	CBr3	−345.19	1	1
92	C sp3	N2OF(+)	−1875.95	1	1
93	C sp3	N4(+)	−2635.7	3	3
94	C sp3	N3F(+)	−4981.42	2	2
95	C sp3	O4	−2239.99	3	3
96	C sp3	O2F2	−1255.75	1	1
97	C sp3	OF3	−692.57	2	2
98	C sp3	OF2Cl	−768.91	1	1
99	C(-) sp3	C3	−3078.32	2	2
100	C sp2	H2=C	−703.3	255	227
101	C sp2	H2=N	−1694.79	2	2
102	C sp2	HC=C	−563.48	1268	695
103	C sp2	HC=N	−1522.25	64	58
104	C sp2	HC=O	−390.29	115	111
105	C sp2	H=CN	−1024.99	141	103
106	C sp2	HC=N(+)	−5278.26	7	7
107	C sp2	H=CN(+)	−1032.17	4	4
108	C sp2	H=CO	−619.08	54	48
109	C sp2	H=CS	−1228.75	80	61
110	C sp2	H=CF	−547.73	2	2
111	C sp2	H=CCl	−550.31	8	6
112	C sp2	H=CBr	−574.22	2	2
113	C sp2	H=CSi	−1051.13	16	9
114	C sp2	HN=N	−1998.61	45	42
115	C sp2	HN=O	−830.28	12	11
116	C sp2	H=NO	−1583.32	2	2
117	C sp2	HO=O	−410.95	19	19
118	C sp2	H=NS	−2218.79	3	3
119	C sp2	C2=C	−430.98	318	255
120	C sp2	C2=N	−1378.53	82	67
121	C sp2	C2=N(+)	326.77	6	6
122	C sp2	C=CN	−893.41	86	66
123	C sp2	C=CN(+)	−928.07	10	10
124	C sp2	C2=O	−241.97	400	337
125	C sp2	C=CO	−470.12	86	69
126	C sp2	C=CS	−1085.43	56	45
127	C sp2	C=CF	−452.88	7	6
128	C sp2	C=CCl	−418.16	22	13
129	C sp2	C=CBr	−412.66	1	1
130	C sp2	=CN2	−1367.07	11	11
131	C sp2	=CN2(+)	−1387.08	10	10
132	C sp2	CN=N	−1858.11	48	40
133	C sp2	CN=N(+)	−1939.3	6	6
134	C sp2	CN=O	−687.04	310	243
135	C sp2	C=NO	−1412.25	18	16
136	C sp2	=CNO	−980.26	1	1
137	C sp2	=CNO(+)	−1004.7	6	6
138	C sp2	CN=S	−1516.78	7	6
139	C sp2	C=NS	−2037.97	6	6
140	C sp2	=CNS(+)	−1601.01	2	2
141	C sp2	=CNCl	−854.46	1	1
142	C sp2	CO=O	−256.51	1142	872
143	C sp2	CO=O(-)	98.04	51	50
144	C sp2	C=OS	−913.81	7	7
145	C sp2	C=OF	−193.64	3	3
146	C sp2	C=OCl	−202.04	14	11
147	C sp2	C=OBr	−203.56	2	2
148	C sp2	C=OJ	−281.05	2	2
149	C sp2	=COF	−297.83	2	2
150	C sp2	CS=S	−1716.14	3	3
151	C sp2	=CS2	−1853.93	2	1
152	C sp2	=CF2	−413.7	9	8
153	C sp2	=CFCl	−362.02	1	1
154	C sp2	=CCl2	−420.11	7	5
155	C sp2	=CJ2	−544.25	2	1
156	C sp2	N2=N	−2333.01	67	55
157	C sp2	N2=N(+)	583.11	2	2
158	C sp2	N2=O	−1148.85	124	107
159	C sp2	N=NO	−1909.16	3	3
160	C sp2	N2=S	−1999.02	27	25
161	C sp2	N=NS	−2485.54	10	9
162	C sp2	NO=O	−712.7	22	21
163	C sp2	N=OS	−1624.45	1	1
164	C sp2	NO=S	−1586.99	5	5
165	C sp2	=NOS	−2019.32	1	1
166	C sp2	=NOCl	−1416.86	1	1
167	C sp2	NS=S	−2180.9	6	6
168	C sp2	NS=S(-)	−2015.49	4	4
169	C sp2	=NSCl	−2036.68	1	1
170	C sp2	O2=O	−288.27	14	14
171	C sp2	O=OCl	−207.85	4	4
172	C sp2	=OS2	−1589.52	2	2
173	C sp2	S2=S	−2384.68	3	3
174	C aromatic	H:C2	−544	10,741	1946
175	C aromatic	H:C:N	−677.57	176	121
176	C aromatic	H:C:N(+)	−664.15	46	25
177	C aromatic	H:N2	−805.13	12	10
178	C aromatic	:C3	−404.91	496	193
179	C aromatic	C:C2	−412.39	2572	1349
180	C aromatic	C:C:N	−537.55	106	62
181	C aromatic	C:C:N(+)	−537.4	37	21
182	C aromatic	:C2N	−904.12	521	380
183	C aromatic	:C2N(+)	−924.19	323	214
184	C aromatic	:C2:N	−541.18	73	54
185	C aromatic	:C2:N(+)	−537.03	33	18
186	C aromatic	:C2O	−485.35	724	496
187	C aromatic	:C2P	−739.79	9	3
188	C aromatic	:C2S	−1093.91	94	75
189	C aromatic	:C2Si	−977.52	30	11
190	C aromatic	:C2F	−400.21	136	67
191	C aromatic	:C2Cl	−391.36	235	137
192	C aromatic	:C2Br	−393.11	72	50
193	C aromatic	:C2J	−466.27	39	34
194	C aromatic	C:N2	−653.04	5	3
195	C aromatic	:CN:N	−1014.82	17	13
196	C aromatic	:CN:N(+)	−1105.83	3	2
197	C aromatic	:C:NO	−567.84	11	11
198	C aromatic	:C:NCl	−521.23	30	21
199	C aromatic	:C:NBr	−517.98	4	3
200	C aromatic	N:N2	−1126.33	22	14
201	C aromatic	:N2O	−708.43	17	6
202	C aromatic	:N2S	−1372.64	1	1
203	C aromatic	:N2Cl	−639.79	11	10
204	C(+) aromatic	H:N2	915.78	17	17
205	C(+) aromatic	:N3	1847.84	3	3
206	C sp	H#C	−654.9	50	42
207	C sp	C#C	−502.89	198	108
208	C sp	=C2	−532.17	12	11
209	C sp	C#N	−495.27	165	139
210	C sp	C#N(+)	−521.62	4	3
211	C sp	C#N(-)	378.06	6	2
212	C sp	#CN	−1069.64	2	2
213	C sp	=C=N	−1519.98	2	2
214	C sp	=C=O	−281.24	4	3
215	C sp	#CS	−1214.94	2	2
216	C sp	#CCl	−514.93	3	2
217	C sp	#CSi	−1091.51	3	3
218	C sp	N#N	−982.36	4	4
219	C sp	N#N(-)	−144.09	10	5
220	C sp	=N2	−2404.6	2	2
221	C sp	#NO	−648.9	2	2
222	C sp	=N=O	−1216.26	22	16
223	C sp	#NS	−1277.41	1	1
224	C sp	=N=S	−2056.03	2	2
225	C sp	=N=S(-)	−1076.3	2	2
226	N sp3	H2C	218.81	64	56
227	N sp3	H2C(pi)	253.54	334	285
228	N sp3	H2N	−304.07	29	23
229	N sp3	H2N(pi)	−266.71	1	1
230	N sp3	H2S	215.36	9	9
231	N sp3	HC2	814.55	69	63
232	N sp3	HC2(pi)	846.53	138	105
233	N sp3	HC2(2pi)	845.11	253	200
234	N sp3	HCN	288.21	5	3
235	N sp3	HCN(pi)	315.32	41	28
236	N sp3	HCN(+)(pi)	734.53	5	4
237	N sp3	HCN(2pi)	359.34	69	64
238	N sp3	HCN(+)(2pi)	717.66	6	6
239	N sp3	HCO(pi)	520.5	2	2
240	N sp3	HCS(pi)	1015.17	3	3
241	N sp3	HCSi	829.19	5	5
242	N sp3	HN2(2pi)	−176.66	1	1
243	N sp3	HNS	552.34	1	1
244	N sp3	HSi2	850.75	1	1
245	N sp3	C3	1409.08	84	73
246	N sp3	C3(pi)	1429.38	98	84
247	N sp3	C3(2pi)	1430.98	69	52
248	N sp3	C3(3pi)	1421.7	31	23
249	N sp3	C2N	871.27	1	1
250	N sp3	C2N(pi)	896.78	13	11
251	N sp3	C2N(+)(pi)	1320.4	40	25
252	N sp3	C2N(2pi)	954	23	22
253	N sp3	C2N(+)(2pi)	1269.38	12	7
254	N sp3	C2N(3pi)	948.11	9	9
255	N sp3	C2N(+)(3pi)	1230.43	3	3
256	N sp3	C2O	1037.7	3	3
257	N sp3	C2S	584.44	6	3
258	N sp3	C2Si	1437.12	8	6
259	N sp3	C2F(2pi)	−2337.09	1	1
260	N sp3	C2Cl(2pi)	878.7	1	1
261	N sp3	C2Br(2pi)	900.67	1	1
262	N sp3	CN2(2pi)	491.47	9	7
263	N sp3	CN2(+)(2pi)	1183.51	1	1
264	N sp3	CN2(3pi)	550.35	3	3
265	N sp3	CN2(+)(3pi)	774.31	3	3
266	N sp3	CF2	197.51	12	7
267	N sp3	CF2(pi)	997.31	1	1
268	N sp3	Si3	1479.07	1	1
269	N sp2	H=C	760	10	10
270	N sp2	C=C	1411.35	154	133
271	N sp2	C=N	375.86	70	38
272	N sp2	C=N(+)	714.59	35	31
273	N sp2	=CN	866.59	141	117
274	N sp2	=CN(+)	1299.9	5	5
275	N sp2	C=O	421.69	13	12
276	N sp2	=CO	935.48	78	55
277	N sp2	=CS	705.75	2	1
278	N sp2	=CF	0	1	1
279	N sp2	N=N	−82.18	80	41
280	N sp2	N=O	1.35	8	6
281	N sp2	=NO	762.47	2	1
282	N sp2	=NO(+)	1041.44	11	6
283	N sp2	O=O	831.52	9	9
284	N sp2	P=P	−482.14	7	2
285	N aromatic	H2:C(+)	−1025.73	5	3
286	N aromatic	HC:C(+)	−363.24	2	2
287	N aromatic	C2:C(+)	216.63	36	19
288	N aromatic	:C2	214.34	273	189
289	N aromatic	:C:N	41.42	6	3
290	N aromatic	:C:N(+)	2190.8	1	1
291	N(+) sp3	H3C	57.66	47	46
292	N(+) sp3	H2C2	607.96	9	9
293	N(+) sp3	HC3	1364.55	6	4
294	N(+) sp3	C4	1885.72	8	8
295	N(+) sp2	C=CO(-)	5214.75	7	7
296	N(+) sp2	C=NO	442.92	16	8
297	N(+) sp2	C=NO(-)	155.64	16	11
298	N(+) sp2	CO=O(-)	548.28	550	310
299	N(+) sp2	=CO2(-)	−568.22	6	6
300	N(+) sp2	NO=O(-)	−366.72	76	54
301	N(+) sp2	O2=O(-)	188.79	73	37
302	N(+) aromatic	C:C2	698.75	1	1
303	N(+) aromatic	:C2O(-)	234.67	58	40
304	N(+) aromatic	:C:NO(-)	−2193.1	1	1
305	N(+) sp	C#C(-)	−94.07	6	6
306	N(+) sp	#CO(-)	0	4	3
307	N(+) sp	=N2(-)	−542.94	30	26
308	N(-)	C2	−776.85	5	5
309	O	HC	550.37	663	373
310	O	HC(pi)	149.9	795	622
311	O	HN	−183.46	3	3
312	O	HN(pi)	−66.29	29	23
313	O	HO	−35.98	29	26
314	O	HP	−107.27	3	2
315	O	HS	346.8	8	8
316	O	HSi	241.58	1	1
317	O	BC	1904.24	2	2
318	O	C2	1101.66	471	283
319	O	C2(pi)	701.99	896	686
320	O	C2(2pi)	278.25	167	156
321	O	CN(pi)	−291.5	24	18
322	O	CN(+)(pi)	401.59	63	29
323	O	CN(2pi)	131.93	14	14
324	O	CN(+)(2pi)	398.5	1	1
325	O	CO	523.43	120	65
326	O	CO(pi)	113.28	65	29
327	O	CS	457.66	18	9
328	O	CP	542.76	10	4
329	O	CP(pi)	91.26	3	1
330	O	CSi	708.96	54	21
331	O	CSi(pi)	318.69	38	15
332	O	N2(2pi)	−65.35	15	14
333	O	N2(+)(2pi)	−220.1	5	5
334	O	OSi	106.92	8	4
335	O	Si2	400.13	11	3
336	P3	C3	124.54	3	3
337	P4	C3=O	−243.18	1	1
338	P4	C3=S	−373.61	1	1
339	P4	C2O=O	−169.24	1	1
340	P4	CO2=O	197.04	1	1
341	P4	CO2=O(-)	−394.07	1	1
342	P4	N=NCl2	0	7	2
343	P4	O3=O	14.1	4	4
344	S2	HC	−88.46	47	42
345	S2	HC(pi)	−58.54	10	10
346	S2	C2	690.55	78	66
347	S2	C2(pi)	714.51	26	21
348	S2	C2(2pi)	750.83	88	82
349	S2	CN(pi)	−618.03	1	1
350	S2	CS	42.29	18	9
351	S2	CS(pi)	53.77	16	8
352	S2	N2	25.26	1	1
353	S2	N2(2pi)	0	1	1
354	S2	NS	−291.87	2	1
355	S4	C2=O	849.53	8	8
356	S4	C2=O2	1073.53	43	43
357	S4	CN=O2	−41.35	11	11
358	S4	CO=O2	216.14	3	3
359	S4	CO=O2(-)	777.27	2	2
360	S4	C=O2S	394.52	2	1
361	S4	N2=O2	558.49	1	1
362	S4	NO=O2	−918.69	1	1
363	S4	O2=O	−92.99	5	5
364	S4	O2=O2	116.23	4	4
365	S4	O2=O2(-)	−556.38	4	4
366	S4	O=O2F	−470.05	1	1
367	S4	O=O2Cl	−463.63	1	1
368	Si	H3C	−740.19	4	4
369	Si	H2C2	12.42	2	2
370	Si	HC3	602.13	29	29
371	Si	HC2Cl	67.18	1	1
372	Si	HCCl2	−100.05	1	1
373	Si	HN3	−2430.7	1	1
374	Si	HO3	−931.42	1	1
375	Si	C4	1327.16	15	15
376	Si	C3N	317.05	15	12
377	Si	C3O	813.97	12	12
378	Si	C3Cl	1013.39	1	1
379	Si	C3Br	1000.85	1	1
380	Si	C2O2	285.19	16	8
381	Si	C2Cl2	592.69	3	3
382	Si	CO3	−235.18	16	16
383	Si	CCl3	145.43	1	1
384	Si	O4	−763.98	7	7
385	H	H Acceptor	0.27	241	188
386	H	.H	−5.79	381	142
387	H	..H	−1.31	4908	1297
388	Angle60		−35.25	405	118
389	Angle90		−24.51	321	66
390	Angle102		−4.65	1663	451
A	Based on	Valid groups	267		5030
B	Goodness of fit	R2	1		4886
C	Deviation	Average	13.66		4886
D	Deviation	Standard	18.12		4886
E	K-fold cv	K	10		4790
F	Goodness of fit	Q2	1		4790
G	Deviation	Average (cv)	14.44		4790
H	Deviation	Standard (cv)	19.16		4790