gpop6mrtcalculates reduced moments of inertia and rotational constants for multiple intramolecular rotations, for pre-examination purpose. It reads a pre-processed GPOP-format file,
basename.gpo, and multiple rotor specification file,
basename.mrt, and prints output to standard output.
gpop6irtand it calculates the reduced moments of inertia as well as the coupling analysis of the intramolecular rotors. This treatment is still experimental and has not been implemented in
gpop3tstand the tools which use its output (
|1)||A GPOP-format file, |
|2)||An multiple internal rotor input file, |
moi1input is the same as that in
gpop6irtprogram, while the moiety-2 is specified by the pivot atom only. The sample input specifies the rotation around C–C bond and that around C–C bond.
1:2-8-9 z1:2-8-9 x1:2-8-9 y1:2-8-9The first and the second lines are identical, and specifies a moiety consisting of H2, O8, and H9 rotating around C1-H2 axis. Here, the z-axis is defined by the two pivot atoms, C1 and H2. The x-axis is defined so as it pass through the center of mass of the moiety, and y-axis perpendicular to both z- and x- axes. The third line specifies the rotation around the axis parallel to x-axis and passing through the pivot, H2. In other words, this is a out of plane C1-H2-O8 bending (wagging). Similarly, the fourth line specifies the rotation around the axis parallel to y-axis and passing through the pivot, H2, or the C1-H2-O8 in-plane bending (rocking).
v1:2-8-9|3-4 p1:2-8-9|3-7:4-6 i1:2-8-9|0:0:1v-option: The input beginning with 'v' specifies the rotation axis direction by the vector connecting two atoms specified after '|'. The first input line above specifies the rocking vibration of H2-O8-H9 moiety.
----- Uncoupled Properties ----- ucR#1: I= 2.55110 B= 6.60799 1 (0.801) 2 (0.595) 8 (0.150) ucR#2: I= 2.55110 B= 6.60799 1 (0.801) 2 (0.595) 8 (0.150)which are same as those reported by
gpop6irtbut in concise format.
DSYEV info:0 lw-opt:68.000 ----- Coupling Calculation Results ----- cpR#1: I= 2.02510 B= 8.32433 vec= -0.707 0.707 cpR#2: I= 3.07709 B= 5.47843 vec= 0.707 0.707 ----- Coupled - most resembling vibrations ----- cpR#1: 2 (0.994) 8 (0.251) 3 (0.250) freq=128.193 cpR#2: 1 (1.000) 7 (0.042) 20 (0.025) freq=115.293The first line is a diagnostic message for DSYEV subroutine in LAPACK, which does not need to be care usually. The coupling calculation results show that the two input localized rotations couples with 1:1 ratio, and the resultant orthogonal roational coordinates and corresponding reduced moments of inertia are;
----- diagnostic of coupling ----- ----- Decoupled Frequencies ----- ucR#1: 120.578 ucR#2: 120.578 ----- Partition Function Correction Factor ----- 0.979Decoupled frequencies are inversely calculated vibrational frequencies for uncoupled (localized) internal rotations. Because of the full symmetry of two local internal rotations, the results gave two identical frequencies for these two equivalent motion. The partition function correction factor must be used when calculating the partition function with localized approximation, and thus it is a measure of the strength of coupling.
|||J. E. Kilpatrick and K. S. Pitzer, J. Chem. Phys. 17, 1064 (1949).|