Esp 8266 - 01 module unable to flash or communicate
Well, first you have to make sure that the connections are proper:


Since PC is talking to ESP8266 via Serial Terminal of Arduino: Rx --> Rx , Tx --> Tx thru 3.3 V voltage divider  as ESP8266 is 3.3 V device while serial voltages are 5V from Arduino FTDI.
CHPD, RST --> 3.3 V, GPIO0, GND --> GND
Much better to use external supply (other than 3.3 V of Arduino) for ESP8266 as it is power hungry at times.
Make sure all ground connections are correct.


My ESP8266 has two LEDs. I guess yours have too.

Check:


If Blue LED of ESP8266 blinked 2-3 times quickly and went OFF. 
If Red LED lighted up and stays ON. if it does, your ESP8266 chip is working fine. Good for you! 
If the Blue LED didnt blink or if it stays ON, Hang on! Your firmware may be corrupt and you will need to re-flash the firmware of ESP8266.here's one method I used in past


If everything is okay by now, go ahead.

Finding baudrate:


You can find the default baudrate of ESP8266 by trial and error. Send 'AT' command in different baudrates until you get 'OK' response in the Serial terminal.
You can then configure baudrate to the required value. Go thru AT commands