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; Parameters for POPC (2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine)
; To be used in conjunction with the GROMOS 54a7 forcefield files.
; Please cite the following references when using this topology:
; Poger D, van Gunsteren WF & Mark AE (2010) J. Comput. Chem. 31(6), 1117-1125
; Poger D & Mark AE (2010) J. Chem. Theory Comput. 6(1), 325-336

[ moleculetype ]
; Name   nrexcl
POPC     3

[ atoms ]
;  nr  type  resnr  resid  atom  cgnr  charge    mass    total_charge
    1  CH3p    1    POPC    CN1    1    0.400  15.0350 
    2  CH3p    1    POPC    CN2    1    0.400  15.0350 
    3  CH3p    1    POPC    CN3    1    0.400  15.0350 
    4    NL    1    POPC    NTM    1   -0.500  14.0067 
    5   CH2    1    POPC     CA    1    0.300  14.0270      ;  1.000
    6   CH2    1    POPC     CB    2    0.400  14.0270 
    7    OA    1    POPC     OA    2   -0.800  15.9994 
    8     P    1    POPC      P    2    1.700  30.9738 
    9    OM    1    POPC     OB    2   -0.800  15.9994 
   10    OM    1    POPC     OC    2   -0.800  15.9994 
   11    OA    1    POPC     OD    2   -0.700  15.9994      ; -1.000
   12   CH2    1    POPC     CC    3    0.400  14.0270 
   13   CH1    1    POPC     CD    3    0.300  13.0190 
   14    OE    1    POPC     OE    3   -0.700  15.9994 
   15     C    1    POPC    C1A    3    0.700  12.0110 
   16     O    1    POPC     OF    3   -0.700  15.9994      ;  0.000
   17   CH2    1    POPC    C1B    4    0.000  14.0270      ;  0.000
   18   CH2    1    POPC    C1C    5    0.000  14.0270      ;  0.000
   19   CH2    1    POPC    C1D    6    0.000  14.0270      ;  0.000
   20   CH2    1    POPC    C1E    7    0.000  14.0270      ;  0.000
   21   CH2    1    POPC    C1F    8    0.000  14.0270      ;  0.000
   22   CH2    1    POPC    C1G    9    0.000  14.0270      ;  0.000
   23   CH2    1    POPC    C1H   10    0.000  14.0270      ;  0.000
   24   CR1    1    POPC    C1I   11    0.000  13.0190      ;  0.000  ; double bond
   25   CR1    1    POPC    C1J   12    0.000  13.0190      ;  0.000  ; double bond
   26   CH2    1    POPC    C1K   13    0.000  14.0270      ;  0.000
   27   CH2    1    POPC    C1L   14    0.000  14.0270      ;  0.000
   28   CH2    1    POPC    C1M   15    0.000  14.0270      ;  0.000
   29   CH2    1    POPC    C1N   16    0.000  14.0270      ;  0.000
   30   CH2    1    POPC    C1O   17    0.000  14.0270      ;  0.000
   31   CH2    1    POPC    C1P   18    0.000  14.0270      ;  0.000
   32   CH2    1    POPC    C1Q   19    0.000  14.0270      ;  0.000
   33   CH3    1    POPC    C1R   20    0.000  15.0350      ;  0.000
   34   CH2    1    POPC     CE   21    0.500  14.0270 
   35    OE    1    POPC     OG   21   -0.700  15.9994 
   36     C    1    POPC    C2A   21    0.800  12.0110 
   37     O    1    POPC     OH   21   -0.600  15.9994      ;  0.000
   38   CH2    1    POPC    C2B   22    0.000  14.0270      ;  0.000
   39   CH2    1    POPC    C2C   23    0.000  14.0270      ;  0.000
   40   CH2    1    POPC    C2D   24    0.000  14.0270      ;  0.000
   41   CH2    1    POPC    C2E   25    0.000  14.0270      ;  0.000
   42   CH2    1    POPC    C2F   26    0.000  14.0270      ;  0.000
   43   CH2    1    POPC    C2G   27    0.000  14.0270      ;  0.000
   44   CH2    1    POPC    C2H   28    0.000  14.0270      ;  0.000
   45   CH2    1    POPC    C2I   29    0.000  14.0270      ;  0.000
   46   CH2    1    POPC    C2J   30    0.000  14.0270      ;  0.000
   47   CH2    1    POPC    C2K   31    0.000  14.0270      ;  0.000
   48   CH2    1    POPC    C2L   32    0.000  14.0270      ;  0.000
   49   CH2    1    POPC    C2M   33    0.000  14.0270      ;  0.000
   50   CH2    1    POPC    C2N   34    0.000  14.0270      ;  0.000
   51   CH2    1    POPC    C2O   35    0.000  14.0270      ;  0.000
   52   CH3    1    POPC    C2P   36    0.000  15.0350      ;  0.000
; total charge of the molecule:   0.000

[ bonds ]
;  ai   aj  funct   c0         c1
    1    4    2   gb_21
    2    4    2   gb_21
    3    4    2   gb_21
    4    5    2   gb_21
    5    6    2   gb_27
    6    7    2   gb_18
    7    8    2   gb_28
    8    9    2   gb_24
    8   10    2   gb_24
    8   11    2   gb_28
   11   12    2   gb_18
   12   13    2   gb_27
   13   14    2   gb_18
   13   34    2   gb_27
   14   15    2   gb_10
   15   16    2   gb_5
   15   17    2   gb_23
   17   18    2   gb_27
   18   19    2   gb_27
   19   20    2   gb_27
   20   21    2   gb_27
   21   22    2   gb_27
   22   23    2   gb_27
   23   24    2   gb_27
   24   25    2   gb_10 ; double bond
   25   26    2   gb_27
   26   27    2   gb_27
   27   28    2   gb_27
   28   29    2   gb_27
   29   30    2   gb_27
   30   31    2   gb_27
   31   32    2   gb_27
   32   33    2   gb_27
   34   35    2   gb_18
   35   36    2   gb_10
   36   37    2   gb_5
   36   38    2   gb_23
   38   39    2   gb_27
   39   40    2   gb_27
   40   41    2   gb_27
   41   42    2   gb_27
   42   43    2   gb_27
   43   44    2   gb_27
   44   45    2   gb_27
   45   46    2   gb_27
   46   47    2   gb_27
   47   48    2   gb_27
   48   49    2   gb_27
   49   50    2   gb_27
   50   51    2   gb_27
   51   52    2   gb_27

[ pairs ]
;  ai   aj  funct  ;  all 1-4 pairs but the ones excluded in GROMOS itp
    1    6    1
    2    6    1
    3    6    1
    4    7    1
    5    8    1
    6    9    1
    6   10    1
    6   11    1
    7   12    1
    8   13    1
    9   12    1
   10   12    1
   11   14    1
   11   34    1
   12   15    1
   12   35    1
   13   16    1
   13   17    1
   13   36    1
   14   18    1
   14   35    1
   15   19    1
   15   34    1
   16   18    1
   17   20    1
   18   21    1
   19   22    1
   20   23    1
   21   24    1
   22   25    1
   24   27    1
   25   28    1
   26   29    1
   27   30    1
   28   31    1
   29   32    1
   30   33    1
   34   37    1
   34   38    1
   35   39    1
   36   40    1
   37   39    1
   38   41    1
   39   42    1
   40   43    1
   41   44    1
   42   45    1
   43   46    1
   44   47    1
   45   48    1
   46   49    1
   47   50    1
   48   51    1
   49   52    1

[ angles ]
;  ai   aj   ak  funct   angle     fc
    1    4    2    2    ga_13
    1    4    3    2    ga_13
    1    4    5    2    ga_13
    2    4    3    2    ga_13
    2    4    5    2    ga_13
    3    4    5    2    ga_13
    4    5    6    2    ga_15
    5    6    7    2    ga_15
    6    7    8    2    ga_26
    7    8    9    2    ga_14
    7    8   10    2    ga_14
    7    8   11    2    ga_5
    8   11   12    2    ga_26
    9    8   10    2    ga_29
    9    8   11    2    ga_14
   10    8   11    2    ga_14
   11   12   13    2    ga_15
   12   13   14    2    ga_13
   12   13   34    2    ga_13
   13   14   15    2    ga_22
   13   34   35    2    ga_15
   14   13   34    2    ga_13
   14   15   16    2    ga_31
   14   15   17    2    ga_16
   15   17   18    2    ga_15
   16   15   17    2    ga_35
   17   18   19    2    ga_15
   18   19   20    2    ga_15
   19   20   21    2    ga_15
   20   21   22    2    ga_15
   21   22   23    2    ga_15
   22   23   24    2    ga_15
   23   24   25    2    ga_27 ; C1H-C1I=C1J
   24   25   26    2    ga_27 ; C1I=C1J-C1K
   25   26   27    2    ga_15
   26   27   28    2    ga_15
   27   28   29    2    ga_15
   28   29   30    2    ga_15
   29   30   31    2    ga_15
   30   31   32    2    ga_15
   31   32   33    2    ga_15
   34   35   36    2    ga_22
   35   36   37    2    ga_31
   35   36   38    2    ga_16
   36   38   39    2    ga_15
   37   36   38    2    ga_35
   38   39   40    2    ga_15
   39   40   41    2    ga_15
   40   41   42    2    ga_15
   41   42   43    2    ga_15
   42   43   44    2    ga_15
   43   44   45    2    ga_15
   44   45   46    2    ga_15
   45   46   47    2    ga_15
   46   47   48    2    ga_15
   47   48   49    2    ga_15
   48   49   50    2    ga_15
   49   50   51    2    ga_15
   50   51   52    2    ga_15

[ dihedrals ]
; GROMOS improper dihedrals
;  ai   aj   ak   al  funct   angle     fc
   13   14   34   12    2     gi_2 ; asymmetric atom CD
   15   14   16   17    2     gi_1 ; planarity of sn-2 carbonyl
   23   24   25   26    2     gi_1 ; planarity of the double bond
   36   35   37   38    2     gi_1 ; planarity of sn-1 carbonyl

[ dihedrals ]
;  ai   aj   ak   al  funct    ph0      cp     mult
    1    4    5    6    1      gd_29
    4    5    6    7    1      gd_4
    4    5    6    7    1      gd_36
    5    6    7    8    1      gd_29
    6    7    8   11    1      gd_20
    6    7    8   11    1      gd_27
    7    8   11   12    1      gd_20
    7    8   11   12    1      gd_27
    8   11   12   13    1      gd_29
   11   12   13   34    1      gd_34
   12   13   14   15    1      gd_29
   12   13   34   35    1      gd_34
   13   14   15   17    1      gd_13
   13   34   35   36    1      gd_29
   14   15   17   18    1      gd_40
   15   17   18   19    1      gd_34
   17   18   19   20    1      gd_34
   18   19   20   21    1      gd_34
   19   20   21   22    1      gd_34
   20   21   22   23    1      gd_34
   21   22   23   24    1      gd_34
   22   23   24   25    1      gd_40 ; C1G-C1H-C1I=C1J
   24   25   26   27    1      gd_40 ; C1I=C1J-C1K-C1L
   25   26   27   28    1      gd_34
   26   27   28   29    1      gd_34
   27   28   29   30    1      gd_34
   28   29   30   31    1      gd_34
   29   30   31   32    1      gd_34
   30   31   32   33    1      gd_34
   34   35   36   38    1      gd_13
   35   36   38   39    1      gd_40
   36   38   39   40    1      gd_34
   38   39   40   41    1      gd_34
   39   40   41   42    1      gd_34
   40   41   42   43    1      gd_34
   41   42   43   44    1      gd_34
   42   43   44   45    1      gd_34
   43   44   45   46    1      gd_34
   44   45   46   47    1      gd_34
   45   46   47   48    1      gd_34
   46   47   48   49    1      gd_34
   47   48   49   50    1      gd_34
   48   49   50   51    1      gd_34
   49   50   51   52    1      gd_34