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Table 1: Characteristics of superconductors
Parameter (*)	Re	W	Ta	Hf	Mo	Nb	V	Ti	Al
Atomic Number	75	74	73	72	42	41	23	22	13
Atomic Weight	186.2	183.85	180.948	178.49	95.94	92.906	50.941	47.90	26.982
Density (gm cm³)	21.02	19.25	16.67	13.28	10.22	8.58	6.09	4.51	2.70
Crystal structure	hcp	bcc	bcc	hcp	bcc	bcc	bcc	hcp	fcc
Bulk Modulus (GPa)	370	310	200	110	230	170	160	110	76
Melting Point (K)	3453	3693	3253	2500	2888	2740	2175	1940	933
Boiling Point (K)	5900	5828	5731	4876	4912	5017	3680	3560	2792
First Ionization Potential (eV)	7.87	7.89	7.98	7	7.18	6.77	6.74	6.83	5.98
Resistivity at 300 K(Ω-m) 10^-8	18.6	5.28	13.2	33.1	5.34	14.5	19.9	43.1	2.74
Resistivity at 10 K(Ω-m) 10^-9	-	0.0014	>0.102	10.02	0.0088	-	0.145	3.5	-
Critical Temperature (K)	1.697	0.0154	4.47	0.128	0.915	9.25	5.40	0.42	1.175
Energy Gap Δ(meV)	0.39	0.003	o.7	0.019	0.139	1.5	0.82	0.06	0.17
Thermal conductivity (W m^-1 K^-1)	48	170	57	23	139	54	31	22	235
Lin. thermal expansion coef. (K^-1) 10⁶	6.2	4.5	6.3	5.9	4.8	7.3	8.4	8.6	23.1
Specific Heat Cp (J g^-1 K^-1)	0.137	0.132	0.14>	0.144	0.251	0.265	0.489	0.520	0.904
Reflectivity (%) at 1 μm	-	62	78	-	58	-	61	-	71

*Data unless specified is at 300 K

Table 2: X-ray Characteristics of superconductors
Parameter (*)	Re	W	Ta	Hf	Mo	Nb	V	Ti	Al
Atomic Number	75	74	73	72	42	41	23	22	13
K-Shell Energy (keV)	71.676	69.525	67.416	65.351	20.000	18.986	5.465	4.966	1.559
L1-Shell Energy (KeV)	12.527	12.100	11.682	11.271	2.866	2.698	0.627	0.561	0.118
L2-shell Energy (keV)	11.959	11.544	11.136	10.739	2.625	2.465	0.520	0.461	0.073
L3-shell Energy (keV)	10.535	10.207	9.881	9.561	2.520	2.371	0.512	0.454	0.072
Kα₁ Line Energy (keV)	61.140	59.318	57.532	55.790	17.479	16.615	4.952	4.511	1.487
Kα₂ Line Energy (keV)	59.718	57.982	56.277	54.611	17.374	16.521	4.945	4.505	1.486
Kβ₁ Line Energy (keV)	69.310	67.244	65.223	63.234	19.608	18.622	5.427	4.932	1.558
Lα₁ Line Energy (keV)	8.653	8.398	8.146	7.899	2.293	2.166	0.511	0.452	0.043
Lα₂ Line Energy (keV)	8.586	8.335	8.088	7.845	2.290	2.163	0.511	0.452	0.043
Lβ₁ Line Energy (keV)	10.010	9.672	9.343	9.023	2.395	2.257	0.519	0.458	0.072
K-Shell Fluorescent Yield (%)	95.9	95.7	95.6	95.4	76.4	74.8	25.0	21.9	3.6
L-Shell Fluorescent Yield (%)	30	31	28	26	8	7	0.6	0.3	0.2

Table 3: Characteristics of Materials suitable for coatings or contacts
Parameter (*)	Al	Cr	Ni	Pd	Ag	In	Pt	Au
Atomic Number	13	24	28	46	47	49	78	79
Density (kg m^-3)	2700	7140	8908	12023	10490	7310	21090	19300
Crystal structure	fcc	bcc	fcc	fcc	fcc	tetrag.	fcc	fcc
Bulk Modulus (GPa)	76	160	180	180	100	41	230	220
Mohs Hardness (MPa)	2.75	8.5	4.0	4.75	2.5	1.2	3.5	2.5
Melting Point (K)	933	2180	1728	1828	1235	430	2041	1337
Boiling Point	2792	2944	3186	3236	2435	2345	4098	3129
Number of atoms (m^-3) 10²⁸	6.02	8.33	9.14	6.80	5.85	3.83	6.62	5.9
Ionization Potential (eV)	5.986	6.766	7.635	8.34	7.576	5.786	9.0	9.225
Electronegativity (eV )	1.5	1.6	1.8	2.2	1.9	1.7	2.2	2.4
Electron Work Function (eV)	4.28	4.5	5.15	5.12	4.26	4.12	5.65	5.1
Resistivity at 300 K(Ω-m) 10^-8	2.65	12.7	7	10	1.6	8	10.6	2.2
Thermal conductivity (W/m K)	235	94	91	72	430	82	72	320
Lin. thermal expansion coef. (K^-1) 10⁶	23	6.2	13.4	11.8	18.9	32.1	8.8	14.2
Debye Temperature (K)	394	460	375	275	215	129	230	170
Specific Heat Cp (J g^-1 ^oC^-1)	0.9	0.449	0.444	0.244	0.232	0.233	0.13	0.128
Reflectivity (%) at 1 μm	71	-	72	72	97	-	73	95

*Data unless specified is at 300 K

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