Online-only Table 1.

Comparison of current density functional (J-DFT) predictions with experimental (Exp) and previously (Prev.-DFT) reported Electric Field Gradient, V_zz (10²¹Vm⁻²) data.

Material	JID	Atom	|Vzz (Exp)|	|Vzz (J-DFT)|	|Vzz (Prev.-DFT)|	|Δ|	|Δ%|
Cl2	855	Cl	55.1858	52.85	54.2343	2.33	4.22
Br2	840	Br	95.6958	88.86	94.4443	6.83	7.14
I2	895	I	113.0058	108.70	119.0143	4.30	3.81
Be	25056	Be	0.04459	0.072	0.0660	0.028	63.64
Mg	14840	Mg	0.04859	0.079	0.0460	0.031	64.58
Sc	996	Sc	0.3859	1.78	0.9660	1.40	368.4
Ti	14815	Ti	1.6159,61	1.64	1.7560	0.03	1.86
Co	858	Co	2.959	0.52	0.2960	2.38	82.06
Zn	1056	Zn	3.4859	5.62	4.2960	2.14	61.50
Zr	14612	Zr	4.4059	3.50	4.1460	0.90	20.45
Tc	1020	Tc	1.8359	1.67	1.7460	0.16	8.74
Ru	987	Ru	0.9759	1.52	1.6260	0.55	56.70
Cd	14832	Cd	6.5059	7.56	8.1360	1.06	16.31
La	910	La	1.6259	2.24	0.9160	0.62	38.27
Hf	14590	Hf	7.3359	8.87	8.1260	1.54	21.01
Re	981	Re	5.1259	6.14	6.4960	1.02	19.92
Os	952	Os	4.1659	6.00	7.0260	1.84	44.23
BI3	3630	I	71.2962	68.98	—	2.31	3.24
CF3I	32512	I	124.3463	123.22	—	1.12	0.90
CIN	5758	I	157.2164	151.0	—	6.21	3.95
NaNO2	1429	Na	0.43865	0.552	0.57566	0.114	26.03
NaNO2	1429	N	11.1065	12.194	11.77266	1.094	9.86
Cu2O	1216	Cu	9.8067	6.47	6.76566	3.33	33.98
TiO2	10036	Ti	2.2168	2.098	2.26966	0.112	5.07
TiO2	10036	O	2.3868	2.21	2.23566	0.17	7.14
SrTiO3	8082	O	1.6269	1.24	1.0070	0.38	23.46
BaTiO3	8029	O	2.4669	3.56	2.3570	1.10	44.72
Li3N	1375	N	1.0471	1.25	1.0966	0.21	20.19
Li3N	1375	Li(2c)	0.3071	0.225	0.29166	0.075	25.00
Li3N	1375	Li(1b)	0.6071	0.50	0.61666	0.144	24.00
FeSi	8178	Fe	4.4572,73	4.84	4.9243	0.39	8.76
FeS2 (marcasite)	2142	Fe	3.074	2.93	3.2143	0.07	2.33
FeS2 (pyrite)	9117	Fe	3.6674	3.51	3.4043	0.15	4.10
2H-MoS2	54	Mo	7.0939,40	7.70	—	0.61	8.60
2H-MoS2	54	S	5.5439,40	5.33	—	0.21	3.80
2H-WS2	72	S	4.8239,40	4.53	—	0.29	6.22
CaGa2	16464	Ga	4.4475	3.55	3.7776	0.89	20.05
SrGa2	14853	Ga	5.2275	2.54	4.1376	2.68	51.34
BaGa2	19628	Ga	4.4875	5.10	4.3876	0.62	13.84
NaGa4	14728	Ga(e)	6.4976	5.20	6.1876	1.29	19.88
NaGa4	14728	Ga(d)	4.6476	4.33	4.4476	0.31	6.68
CaGa4	20533	Ga(e)	2.8976	2.67	2.8076	0.22	7.61
CaGa4	20533	Ga(d)	4.8776	4.99	4.7376	0.12	2.46
SrGa4	20206	Ga(e)	2.5176	1.67	2.2476	0.84	33.47
SrGa4	20206	Ga(d)	5.9576	5.31	5.6476	0.64	10.76
TaP	79643	Ta	3.0077	2.5	3.5477	0.50	16.67
UAs2	19797	U	15.078	9.7	13.0357	5.3	35.3
MAD						1.17	—
MAPD						-	28.90

The MAD (Mean Absolute Deviation), and MAPD (Mean Absolute Percentage Difference) values are calculated for the whole data. Details of each material are provided at its corresponding webpage. Please look into the references (and references therein) for experimental and previously calculated data.