Fault detection and analysis of bistable rotaxane molecular electronic switch - A simulation approach

Figures & data

Figure 1. Chemical structure of bistable rotaxane. (a) Dumbbell component & CBPQT⁴⁺ ring of Rotaxane molecular switch, (b) OFF state of Rotaxane switch (CBPQT⁴⁺ ring at TTF site), (c) ON state of rotaxane switch (CBPQT⁴⁺ ring at DNP site).

Figure 2. Completely optimized bistable rotaxane (a) Dumbbell alone (b) CBPQT⁴⁺ Ring alone (c) GSCC/OFF state (CBPQT⁴⁺ ring at TTF site) and (d) MSCC/ON state (CBPQT⁴⁺ ring at DNP).

Figure 3. CBPQT⁴⁺ ring positioned between the MPTTF and DNP.

Figure 4. Ring positioned between (a) MPTTF and one end of the dumbbell (b) DNP and the other end of dumbbell.

Figure 5. Total molecular energy (Hartree) of rotaxane molecule with respect to the distance (Å) moved by the ring along the dumbbell.

Table 1. Variation in total molecular energy of bistable rotaxane w.r.t position of CBPQT⁴⁺ ring.

Distance of the ring over dumbbell w.r.t C of Pyrole (Å)	Total Molecular energy (Hartree)	Total Molecular energy (eV)
Undistorted / Mechanically coupled geometry
−4.7	−9698.55	−263 917.07
0	−9700.51	−263 970.41
1.77	−9700.54	−263 971.06
2.61	−9700.53	−263 970.83
3.91	−9700.47	−263 969.16
15.88	−9700.39	−263 966.94
18.75	−9699.95	−263 955.14
19.18	−9700.13	−263 959.89
19.64	−9700.14	−263 960.13
Distorted / Chemically coupled geometry
8.72	−9699.81	−263 951.29
9.07	−9690.68	−263 702.73
10.14	−9699.43	−263 940.88
10.21	−9699.48	−263 942.32
11.16	−9698.93	−263 927.25
11.31	−9697.35	−263 884.38
11.32	−9697.56	−263 890.03
12.5	−9697.96	−263 901.00
12.51	−9697.04	−263 875.83
12.68	−9698.81	−263 924.06

Table 2. Variation in different parameters with respect to the position of CBPQT⁴⁺ ring.

Distance of the ring over dumbbell w.r.t C of Pyrole in MPTTF (Å)	Difference in total molecular energy (eV) with respect to GSCC energy	Distance between the ring and dumbbell (Å)	Energy Band gap (eV)	Ionisation Energy (eV)
Undistorted Geometry
−4.7	53.99	3.52	0.876	10.034
0	0.65	3.37	1.41	10.211
1.77	0	3.75	1.44	10.334
2.61	0.23	3.69	1.49	10.228
3.91	1.9	3.43	1.26	10.247
15.88	4.13	3.74	1.41	10.119
18.75	15.92	3.54	2.32	9.972
19.18	11.18	3.58	1.31	9.924
19.64	10.94	3.65	0.66	9.78
Distorted Geometry
8.72	19.77	1.05	1.75	10.62
9.07	268.34	1.07	3	11.04
10.14	30.18	1.31	2.52	11.52
10.21	28.74	1.06	1.66	10.66
11.16	43.82	0.73	2.11	11.066
11.31	86.68	1.05	1.99	11.01
11.32	81.03	1.07	2.23	11.009
12.5	70.06	1.05	2.3	11.156
12.51	95.23	1.06	2.18	11.026
12.68	47.00	1.07	2.17	11.182

Figure 6. Comparison of Ionisation energy, Energy band gap and Difference in molecular energy (from GSCC state's energy) at various CBPQT⁴⁺ ring over dumbbell of bistable rotaxane.