Your Molecular Formula

 
List of allowed groups

FWHM:
Resolution:
Apply Gaussian:
 
Reference version:

FWHM = ΔM
(Peak Full Width at Half-Maximum)

Resolution = M / ΔM

 
 

R Examples

Retrieving information for a molecular formula

library(rjson)

mf="C10H20Cl2"

query <- paste("http://www.chemcalc.org/chemcalc/mf?mf=",mf,sep="")
resJSON <- fromJSON(paste(readLines(query), collapse=""))

resJSON$em
resJSON$mw

Find possible molecular formula for a specific monoisotopic mass

library(rjson)

target=300
mfRange="C0-100H0-100N0-10O0-10"

query <- paste("http://www.chemcalc.org/chemcalc/em?monoisotopicMass=",target,
   "&mfRange=", mfRange,sep="")
resJSON <- fromJSON(paste(readLines(query), collapse=""))

for (mf.index in 1:length(resJSON$results)) {
   results <- data.frame( "mf"=resJSON$results[[mf.index]]$mf , 
      "em"=resJSON$results[[mf.index]]$em, 
      "error"=resJSON$results[[mf.index]]$error )
   ifelse(!exists('report'),report <- results, report <- rbind(report,results))
}

report[]