Dear LAMMPS users,
I am calculating the rdf of a polymer chain (with 50 repeating units) in water. The solution in very dilute.
The qualitative rdf of a one atom type of polymer is fine but its magnitude is very high. It converges to 20 instead of 1. While rdf of water is OK.
I would like to ask if anybody has an idea what is wrong with this polymer-polymer rdf of such dilute system. Is there something wrong when the code tries to calculate the density in rdf algorithm?
I have used this command:
compute myRDF all rdf 100 3 3 # 3 is one atom type of polymer
fix 10 all ave/time 100 10 1000 c_myRDF file tmp.rdf mode vector
and one fram of tmp.rdf file:
500000 100
1 0.06 0 0
2 0.18 0 0
3 0.3 0 0
4 0.42 0 0
5 0.54 0 0
6 0.66 0 0
7 0.78 0 0
8 0.9 0 0
9 1.02 0 0
10 1.14 0 0
11 1.26 0 0
12 1.38 0 0
13 1.5 0 0
14 1.62 0 0
15 1.74 0 0
16 1.86 0 0
17 1.98 0 0
18 2.1 0 0
19 2.22 0 0
20 2.34 0 0
21 2.46 0 0
22 2.58 0 0
23 2.7 0 0
24 2.82 6.93695 0.004
25 2.94 51.0584 0.036
26 3.06 88.3741 0.096
27 3.18 76.3756 0.152
28 3.3 86.1203 0.22
29 3.42 94.3334 0.3
30 3.54 96.8516 0.388
31 3.66 65.8948 0.452
32 3.78 92.6666 0.548
33 3.9 76.1707 0.632
34 4.02 58.0359 0.7
35 4.14 80.4713 0.8
36 4.26 45.6011 0.86
37 4.38 54.64 0.936
38 4.5 51.7649 1.012
39 4.62 64.6195 1.112
40 4.74 81.0338 1.244
41 4.86 65.4027 1.356
42 4.98 51.1659 1.448
43 5.1 38.1807 1.52
44 5.22 68.8416 1.656
45 5.34 83.1955 1.828
46 5.46 64.7735 1.968
47 5.58 65.5615 2.116
48 5.7 66.2264 2.272
49 5.82 70.0389 2.444
50 5.94 89.1291 2.672
51 6.06 69.1084 2.856
52 6.18 79.4519 3.076
53 6.3 68.1136 3.272
54 6.42 57.5596 3.444
55 6.54 72.2358 3.668
56 6.66 59.7053 3.86
57 6.78 56.4104 4.048
58 6.9 55.6243 4.24
59 7.02 47.0215 4.408
60 7.14 50.8655 4.596
61 7.26 52.3382 4.796
62 7.38 53.6891 5.008
63 7.5 47.0806 5.2
64 7.62 43.709 5.384
65 7.74 28.5498 5.508
66 7.86 28.5778 5.636
67 7.98 29.4576 5.772
68 8.1 48.7733 6.004
69 8.22 44.9101 6.224
70 8.34 36.488 6.408
71 8.46 30.835 6.568
72 8.58 41.2205 6.788
73 8.7 44.4648 7.032
74 8.82 30.497 7.204
75 8.94 33.8257 7.4
76 9.06 31.5913 7.588
77 9.18 40.5912 7.836
78 9.3 35.0851 8.056
79 9.42 34.8187 8.28
80 9.54 33.3421 8.5
81 9.66 27.1976 8.684
82 9.78 29.9952 8.892
83 9.9 23.0802 9.056
84 10.02 22.5307 9.22
85 10.14 24.6836 9.404
86 10.26 28.3026 9.62
87 10.38 22.0192 9.792
88 10.5 26.5231 10.004
89 10.62 24.4596 10.204
90 10.74 17.6979 10.352
91 10.86 26.6651 10.58
92 10.98 18.3056 10.74
93 11.1 21.0465 10.928
94 11.22 15.7777 11.072
95 11.34 22.3103 11.28
96 11.46 26.0466 11.528
97 11.58 25.0981 11.772
98 11.7 24.5859 12.016
99 11.82 19.3504 12.212
100 11.94 26.3165 12.484
the third column which is the rdf of chosen atom converging to 20 !
Thanks in advance for your help,
Best regards,