obenergy: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/obenergy - from package: openbabel

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/obenergy - from package: openbabel

You may install the required package with command apt-get install {package}

Error in other languages:
obenergy: bevel nie gevind nie
obenergy: comandă negăsită
obenergy: comando não encontrado
obenergy: commande introuvable
obenergy: command not found
obenergy: käsku ei ole
obenergy: không tìm thấy lệnh
obenergy: komanda nerasta
obenergy: Kommando nicht gefunden.
obenergy: kommandot finns inte
obenergy: komut yok
obenergy: nie znaleziono polecenia
obenergy: níor aimsíodh an t-ordú
obenergy: no se encontró la orden
obenergy: no s'ha trobat l'ordre
obenergy: opdracht niet gevonden
obenergy: parancs nem található
obenergy: perintah tidak ditemukan
obenergy: príkaz nenájdený
obenergy: příkaz nenalezen
obenergy: команда не найдена
obenergy: командата не е открита
obenergy: 命令找不到
obenergy: コマンドが見つかりません