question about msd/chunk

Hello everyone
I want to block the box in the z direction and calculate the MSD of the A- molecule in the each chunk. I tried to implement it with the MSD /chunk command, which is shown below. But the output file has no data .
compute cc1 group-a chunk/atom bin/1d z lower 0.1

compute myChunk1 group-a msd/chunk cc1

fix mymsd1 group-a ave/time 1 1 50000 c_myChunk1[*] file tmp1.out mode vector
Is there any problem with my command ?
I hope you can give me some advice, thank you very much!

With regards

Please help me. Thank you very much

Did you run for 50,000 steps? With 1 1 50000 in your
fix ave/time command you will only get output (for a single snapshot

of averaging) on step 50000, 100000, etc.

You should also try directly outputting (e.g. to a dump file)

the values of the some of the global array produced by compute msd/chunk
with your thermo output. E.g. on step 0, 10, etc in short run.