Hi Feng,
Thank you for the reply. Is this expected to occur at 0 Angstroms as well?
Thanks,
Kyle
> On Oct 2, 2019, at 8:17 AM, Feng Pan <fpan3.ncsu.edu> wrote:
>
> Hi, Kyle
>
> This is an internal problem for ABMD, it will have some abnormal activity
> near the boundary,
> so just ignore it, you can count the relative free energy from the normal
> region, like 38 or so.
> If you really need the the free energy around 40, set to a larger upper
> limit.
>
> Best
> Feng
>
>> On Tue, Oct 1, 2019 at 5:18 PM Kyle Ghaby <ksg225.nau.edu> wrote:
>>
>> Hello Amber experts,
>>
>> I am using the ABMD “COM_DISTANCE” variable to pull two peptides apart and
>> measure the free energy as a function of peptide distance. I have the ABMD
>> split into four input files over 40 Angstroms. I have pasted the MDin and
>> colvar instructions below for reference. My question is regarding the
>> resulting data. At 40 Angstroms, the maximum distance, the free energy of
>> some of my systems plummets. This data seems abnormal, so I was wondering
>> if any of you have seen this before and if it is a sign of something wrong
>> in my simulation. I’m not sure how I should interpret this since I am
>> looking for the lowest point of free energy but a huge plummet from 39-40
>> Angstroms seems like unrealistic data. I greatly appreciate any help.
>>
>> Thanks,
>> Kyle
>>
>> ABMD instructions:
>> Input file for ABMD
>> &cntrl
>> imin = 0, irest = 0, igb = 0, dielc = 1.0,
>> ntx = 1, ntb = 1, ntt = 3, ntp = 0
>> temp0 = 310.0, tautp = 2.0,
>> tol = 0.00001, ntc = 2, ntf = 2, iwrap = 1
>> cut = 9.0, ibelly = 0, dt = 0.002, gamma_ln=1.0
>> ntpr = 5000,
>> ntwr = 5000,
>> ntwx = 5000,
>> nstlim = 25000000,
>> nscm = 100, infe = 1, ntwprt = 19,
>> ntr = 0, ipol = 0
>> &end
>>
>> &abmd
>>
>> mode = 'FLOODING'
>>
>> timescale = 1.0
>> monitor_freq = 500
>> monitor_file = 'abmd_monitor_1.dat'
>> cv_file = 'cv.dist.in'
>> umbrella_file = 'bias_1.nc'
>>
>> selection_freq = 5000
>> selection_constant = 0.00001
>> selection_epsilon = 0.0
>> wt_temperature = 10000
>> wt_umbrella_file = 'wt_bias_1.nc'
>>
>> /
>> ~
>>
>> My colvar file is as follows: (the two peptides are divided after the
>> 394th atom)
>> &colvar
>> npath = 2, nharm = 1,
>> path = 8.0, 5.0,
>> harm = 10.0
>>
>> cv_type = 'COM_DISTANCE'
>> cv_min = 0.0, cv_max = 40.0, resolution = 1.0
>>
>> cv_ni = 788,
>> cv_i =
>> 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255,256,257,258,259,260,261,262,263,264,265,266,267,268,269,270,271,272,273,274,275,276,277,278,279,280,281,282,283,284,285,286,287,288,289,290,291,292,293,294,295,296,297,298,299,300,301,302,303,304,305,306,307,308,309,310,311,312,313,314,315,316,317,318,319,320,321,322,323,324,325,326,327,328,329,330,331,332,333,334,335,336,337,338,339,340,341,342,343,344,345,346,347,348,349,350,351,352,353,354,355,356,357,358,359,360,361,362,363,364,365,366,367,368,369,370,371,372,373,374,375,376,377,378,379,380,381,382,383,384,385,386,387,388,389,390,391,392,393,394,
>> 0,
>> 395,396,397,398,399,400,401,402,403,404,405,406,407,408,409,410,411,412,413,414,415,416,417,418,419,420,421,422,423,424,425,426,427,428,429,430,431,432,433,434,435,436,437,438,439,440,441,442,443,444,445,446,447,448,449,450,451,452,453,454,455,456,457,458,459,460,461,462,463,464,465,466,467,468,469,470,471,472,473,474,475,476,477,478,479,480,481,482,483,484,485,486,487,488,489,490,491,492,493,494,495,496,497,498,499,500,501,502,503,504,505,506,507,508,509,510,511,512,513,514,515,516,517,518,519,520,521,522,523,524,525,526,527,528,529,530,531,532,533,534,535,536,537,538,539,540,541,542,543,544,545,546,547,548,549,550,551,552,553,554,555,556,557,558,559,560,561,562,563,564,565,566,567,568,569,570,571,572,573,574,575,576,577,578,579,580,581,582,583,584,585,586,587,588,589,590,591,592,593,594,595,596,597,598,599,600,601,602,603,604,605,606,607,608,609,610,611,612,613,614,615,616,617,618,619,620,621,622,623,624,625,626,627,628,629,630,631,632,633,634,635,636,637,638,639,640,641,642,643,644,645,646,647,648,649,650,651,652,653,654,655,656,657,658,659,660,661,662,663,664,665,666,667,668,669,670,671,672,673,674,675,676,677,678,679,680,681,682,683,684,685,686,687,688,689,690,691,692,693,694,695,696,697,698,699,700,701,702,703,704,705,706,707,708,709,710,711,712,713,714,715,716,717,718,719,720,721,722,723,724,725,726,727,728,729,730,731,732,733,734,735,736,737,738,739,740,741,742,743,744,745,746,747,748,749,750,751,752,753,754,755,756,757,758,759,760,761,762,763,764,765,766,767,768,769,770,771,772,773,774,775,776,777,778,779,780,781,782,783,784,785,786,787,788
>> /
>> _______________________________________________
>> AMBER mailing list
>> AMBER.ambermd.org
>> http://lists.ambermd.org/mailman/listinfo/amber
>>
>
>
> --
> Feng Pan
> PostDoc
> Florida State University
> Department of Statistics
> Email: fpan3.ncsu.edu; fpan.fsu.edu
> _______________________________________________
> AMBER mailing list
> AMBER.ambermd.org
> http://lists.ambermd.org/mailman/listinfo/amber
_______________________________________________
AMBER mailing list
AMBER.ambermd.org
http://lists.ambermd.org/mailman/listinfo/amber
Received on Wed Oct 02 2019 - 09:00:02 PDT
